I RING the bell. No-one answers. The leaflet in my hand tells me this grey, slate-covered building - a monastery since 1895 - is the Church of England's "best-kept secret". But I have come to Hampshire to unravel another secret: that of the cult of Jane Austen. The door opens; an ageing hand emerges. Dom Nicholas, a black habit-wearing Benedictine monk, welcomes me to Alton Abbey, his home of 20 years. Aside from the books and bone china, the surroundings are austere, otherworldly, which seems right for a discussion of the woman he reveres as "the universal provider".

Last week, the 19th-century author's novel Pride And Prejudice was revealed as Britain's favourite book. "If you are a human being at all, Jane Austen has something to interest you," says Nicholas. In his case, as a former English teacher, that interest is twofold: there are Austen's elegantly crafted sentences, wrapped tighter than a regency corset; and then there is her spirituality, which courses like a current through her novels. It's there in her reflections on worldly duty, he says, in the theme of self-sacrifice for the sake of a higher cause.

By his own admission, Dom Nicholas is a Janeite, a term first coined by the critic George Saintsbury in 1894 to describe converts to the Austen cult. Like Austen's minister brother Henry, Saintsbury propagated the image of a demure, saintly spinster, who lived selflessly in the country penning "bits of ivory". Rudyard Kipling's 1924 story The Janeites - in which British soldiers find solace from the barbarity of the first world war in Austen's prose - took the term to a wider audience. The idea that Austen - part Mother Mary, part Florence Nightingale - provides manna for the troubled soul is the common thread. Most Janeites these days refer to the author in the present tense, as a living breathing entity, or a family friend. Hers is the mother lode from which adherents continue to draw strength.

"We're all fascinated by her life and her family, the food she would have eaten and the dress she would have worn," says Dom Nicholas. "But that fascination is based on the fact that this young woman, who died at the age of 42, was able to sit down and write such amazing things. Underneath the Jane Austen cultus there is the foremost writer in the English language, who keeps you turning the pages and fulfils your happiest dreams. Can you think of anything better than marrying someone who loves you and whom you love, who has enough money to keep you in comfort and can do a bit of good with that money as well?"

A daughter of Steventon Parish, the last of seven children, Austen came to the Hampshire village of Chawton following her father's death in 1809. It was here she completed her six major novels, reworking those begun in Steventon and composing three more. That Dom Nicholas finds himself these days offering Jane Austen retreats at the abbey is a pleasant, if not divine, irony.

"Someone writing a book on Anglican spirituality came to visit our community a few years back and asked for a quotation by a saint to sum up real spirituality," he says. "I suggested: They had been instructed theoretically in their religion, but never required to bring it into daily practice.' He asked who wrote it. Jane Austen,' I told him, Mansfield Park.'"

The "bird's nest" analogy, whereby Austen plucked details from here, there and everywhere to make a coherent whole, is particularly pleasing to Dom Nicholas, and could equally apply to those who have re-imagined the author on screen. The central conceit of Becoming Jane, the new film starring Anne Hathaway and James McAvoy, is that 20-year-old Austen falls in love with Irish law student Tom Lefroy, on holiday at the nearby village of Ashe while he is studying to take the bar in London. Based on a book of the same name by historian Jon Spence, the theory goes that, with marriage to Lefroy deemed impossible, Austen channelled her creative juices into what would later become Pride And Prejudice. Lefroy, it suggests, re-emerges in the shape of Mr Darcy; he was the prince charming who, in real life at least, didn't come through with the goods.

Much of the premise rests on the surviving letters from Austen to her sister, Cassandra, most of which were destroyed after the author's death. They confirm that the couple met at local balls over a three-week period in 1796, engaging in "every thing most profligate and shocking in the way of dancing and sitting down together". Flirting, yes; true love, maybe not. On one occasion, say the letters, a startled Lefroy ran from the back door of his aunt's house when Austen came to visit. At 90, and by then chief justice in Ireland, he admitted having once felt a "boyish love" for the author, nothing more.

If the exaggeration rankles with die-hard Janeites, Dom Nicholas takes it happily in his stride. "I have a friend who saw 1995's BBC adaptation of Pride And Prejudice and told me enthusiastically that Austen was so wonderfully advanced for 1810," he remembers. "When I asked her to explain, she mentioned the bit with the wet shirt. Of course, that was purely the imagining of a director who thought it would be nice to have a very handsome young man coming out of the water." Referred to interchangeably as "that scene", "the shirt scene", or the "phwoarr scene", the footage of Colin Firth clambering out of a pond, all see-through shirt and mumbled lines, arguably did more for the author than any well-placed turn of phrase.

In today's Chawton, the puddles, though big enough to bathe in, are no match. Timber-framed thatched-roofed houses still abound; others have changed beyond all recognition since Austen's day. But Chawton House - which was inherited by Austen's older brother Edward - still looks the part. Rescued from a state of disrepair by Sandy Learner, of Cisco Systems fortune, it now houses a library of early English women writers, many of whom would have been read by Austen herself. From the mansion's upper windows, views of tree-lined fields stretch into the distance; horses and rabbits graze idly; the sky is reflected in pools of static flood water. It's easy enough to imagine an Elizabeth Bennet wandering around, an Emma Woodhouse plotting mischief for her peers. When it comes to the Jane Austen Society of North America, which holds conventions at the house every two or three years, such sights are almost guaranteed.

"They're really into it," says local historian Jane Hurst. This seems to be an understatement, given her descriptions of these conventions, though any criticism of the cult is couched in careful terms. "The first time I went, there were several Americans completely dressed the part. Unfortunately, the ladies were not young or slim and the gentlemen didn't look much like Mr Darcy. I'd not been to anything like that before and I didn't know whether to laugh or cry. The way people talk about the characters, one doesn't know if they've quite separated fiction from reality."

Along with Steventon, where Austen was born, and Winchester Cathedral, where she is buried, Chawton completes the holy trinity for Janeite pilgrims. Hurst, who has seen visitor numbers in the village rise and fall with each new adaptation of Austen's work, is bracing herself for more. On the heels of Becoming Jane, ITV will air three new adaptations of Austen novels this spring, adding to the slew in recent years.

As well as the plethora of period dramatisations, modern takes have included Clueless, in which Austen's Emma Woodhouse is transported to Beverley Hills, and Bride And Prejudice, where the Indian caste system is substituted for the class divide of Austen's era. Some stray further still. In what is essentially the same character, Colin Firth morphed back into Mr Darcy for Bridget Jones's Diary, no doubt ushered through casting in dripping britches. But despite being where it all first started, Chawton features neither in the books nor the films, and remains a touchstone for purists alone.

"Until fairly recently, most locals were oblivious to the fact that there was a link with Jane Austen here," says Hurst. "A few years back we suddenly noticed a sign on the fringes of Hampshire saying Jane Austen country', which came as news to most people." Despite putting herself forward as secretary of the local branch of the Jane Austen society "like a mug", Hurst differs from other Janeites in that she is decidedly cool on the novels. "They're interesting in the picture they give of life at the time," she says, "but it's a very definite level of society."

It's a moot point. While realist in tone, and viewed as a microcosm of an age, the wider issues of Austen's time - the industrial revolution, King George's impending madness - are never mentioned. Napoleon's advances through Europe, and fervent love letters to Josephine, feature only peripherally in the novels, and are perhaps best remembered locally in the The French Horn pub. Essentially living off the charity of her elder brothers, who were by no means settled financially, Austen would have been as aware of those below her as those above.

"The books had to be set where the ladies were leisured and had spare money," says Hurst. "I don't think she could have survived portraying squalor at that time."

The knock-on effect is that middle-class Austen has been promoted to the aristocracy, conflated and confused with her characters. Beautified on film and beatified by her followers, the myth has given rise to an industry of relics, where bits of her hair, objects she may have touched, take on special, and particular, relevance. Writing on the cusp of the mechanical age, but largely ignoring it, Austen - or at least, her legacy - has benefited from her old-world image.

"She feeds into the industry of the National Trust and the great heritage houses," says Janet Todd, director of the Centre For The Novel at Aberdeen University and editor of Jane Austen In Context. "It's not an image of the age as such but of our fantasy of it, of a place that never was. It spawns almost a whole culture where you can have Jane Austen parties and dinners, Jane Austen cookery books, etiquette manuals, advice books. She's the last great writer you can think of who didn't go on a train, and wasn't photographed. She died young and had she lived she would have done those things."

The red-brick cottage Austen shared with her sister and mother in Chawton reinforces the point: large by modern standards, and not bad for those of the day, it is no Pemberley (Mr Darcy's country estate). Before being bought in the 1940s by the Carpenter family as a memorial to a son killed in the second world war, it housed three separate families, all of whom resented the mounting requests from admirers to see Austen's one-time room.

Current trustee Tom Carpenter introduces himself as "Miss Austen's present-day servant", breaking into uncontrollable titters before showing me inside. A shrine to the author, it has been restored to its regency standard. Objects to be venerated include clothes of the day, the odd bit of muslin and an open-topped carriage once used to transport the Austen women. Artefacts such as her writing table and the bookcase from which she would have read take pride of place, as does a sewing case made for her niece. They may be few, and essentially just pieces of tat, but such is the stuff of icons.

Carpenter dodges the question of whether he is a Janeite with the verbal dexterity of one of Austen's characters. For him, Chawton cottage was exciting only in that it meant a childhood train ride from London to Hampshire to visit his grandfather. His first conscious contact with Austen's world came courtesy of the 1940 film Pride And Prejudice, with Greer Garson and Laurence Olivier, shown at his school on a two wheel cinecam. Watching it forwards was tolerable, he remembers; watching it being rewound at high speed was better for laughs.

"Jane Austen didn't mean anything to me," he admits, "because I never had to read her at school. I think if you come to her books later in life they are funnier and more amusing than they would have been before. It certainly worked for me."

Despite the oft-quoted adage that a single man in possession of a good fortune must be in want of a wife, Carpenter reminds me that in Austen's situation the reverse would have been more likely. "As the second daughter of a country parson, with no money of any sort, her only way onwards and upwards as a young lady would have been to get a wealthy man," he says. "She doesn't say so directly in the letters, but reading between the lines you can say that, at just 20, she must have seen Lefroy as a tremendous opportunity. His was clearly a very astute mind, as was hers, so I wouldn't be surprised if they really hit it off. That said, he may well have thought that she was coming on a bit strong. Forgetting the academic side, and the strict historic side, I expect the film will be a thoroughly good romp."

If so, it will be good for business. Emma Thompson's 1996 adaptation of Sense And Sensibility saw visitor numbers at the cottage double to more than 55,000, and the decade since has seen little let-up. Floors have been bolted down for safety, says Carpenter, although it may be to prevent theft of souvenirs. On busy days, people are waiting for him to open the doors, a situation he says would have been unthinkable before the films of recent years. As "servant" and trust beneficiary, he has rethought his earlier indifference to the author, and now sees her in a different light.

"We used to say that Shakespeare would have a gold medal, Jane Austen silver, with Dickens and Brontë fighting for bronze. Now Austen would get the gold medal, absolutely. In terms of artistic merit, she'd be right at the top because she hits on a formula that really works."

Her use of language, he argues, has endless applications in fields such as advertising and sales. The tribute is well-meant, I know, but sounds strangely secular for a woman near-worshipped as the Madonna without child. While mass media has undoubtedly played its part in the cult, with Austen a commodity to be traded, the true disciples prefer more subtle means of marketing.

"I've got this habit of going away in the summer and taking an Austen book with me," says Denise Luker, who chairs the Hampshire branch of the Jane Austen Society. She pours two cups of tea, all handsome smiles and sobriety. "I leave it wherever I am in the world so that hopefully someone else will pick it up. There's a copy on a cruise liner somewhere round Alaska, several in Italy, one in France, one in Norway. It's my way of spreading the word."

Thanks to Luker's guerrilla tactics, Northanger Abbey will find its way to Greenland this summer; another will be travelling to Antarctica after Christmas. She has read the novels not just once but several times, and her favourites several times more. Experience has shown them to be ice-breakers, a means of making friends. The films, depending on their treatment of Austen, can have the opposite effect. In the age of the prequel and sequel, she knows Hollywood's affair with the author has barely begun. If not quite Anne Hathaway in real life, she hopes such biopics will eventually get to the nub of the real Austen.

"I think we're only now beginning to get underneath things and learn about the real character of the woman," she says. "The topics she broaches in the later books wouldn't have been very PC for her time. Infidelity and her views about marriage were not what a parson's daughter and spinster would have been thought to cover. It's in Mansfield Park that she actually delves into that. You can see she's maturing as a woman and isn't quite the cuddly aunt that her image is about."

Whatever illumination the film provides may be superfluous to those for whom the sun is already shining. Dom Nicholas hopes to get his hands on the DVD of Becoming Jane at some point, but is in no hurry. For him, the visual recreation of the era, the costumes and the mannerisms are what most appeal on celluloid. Whether the film plugs the gaps, or adds new weight to the mythology, is by the by, he says, as the real truth will remain in the text. Keeping his eyes on the source, and not the symptoms, will suffice.

"The Jane Austen industry is balanced on a knife-edge at the moment," says Nicholas. "I have enjoyed every film of one of her novels that I have ever seen and there are things in them that I have loved, but they have been films, they have not been Jane Austen books. Given the choice I reach for Persuasion and open it, I don't put on the video. I wonder how common a reaction that still is and how common that will be as time goes on."

Becoming Jane is released on Friday.