Sir Tom, one of Scotland's most successful entrepreneurs, accused both sides of failing to provide answers to the key questions for voters to decide whether the country should stay in the UK or become independent.
The currency in an independent Scotland and the country's future relationship with Europe and Nato were two crucial areas where more facts were required, the tycoon said.
Sir Tom, who made £290 million when he sold his Sports Division retail chain to JJB in 1998, added: "I think we've had the skirmishes but we've got to get into the real fight and I'm really looking forward to it. I guess I'm impatient for some of the answers."
He added: "I'm your classic swing voter and I'm there to be convinced by either side."
With supporters of independence and the Union jockeying to win the endorsement of key business figures, Sir Tom's comments will make uncomfortable reading for politicians in both camps, who insist their preferred constitutional arrangement would be best for the stewardship of the economy.
His remarks come less than 500 days before the referendum vote on September 18, 2014.
An Ipsos Mori telephone poll yesterday of 1000 people put those against independence at 59% and 31% in favour; the highest support for Scotland staying in the UK since August 2011.
The Ayrshire businessman said: "On the independence side, they need to start coming out with some hard facts to hard questions, and on the Better Together side I would say 'tell me why we're better together, not why we shouldn't be independent'... because we're a pretty stubborn race and if someone keeps telling you you can't do that and you can't do this we might just say, well, yes we can.
"I would rather see a more positive, 'right, here's why we're best with the Union, here's what it's going to be like, here's what we're offering' because if all they're offering is the status quo that's no use.
"People like to know tomorrow will be better than today."
In February, Sir Tom said the No campaigners were digging themselves into a hole if they believed a dual "status quo" and "scare them to death about independence" message would work.
He was also critical of the Scottish Government, saying Alex Salmond had to develop a clearly defined and costed programme for independence in 2014.
Yesterday, he noted: "Alex Salmond is a master of painting the picture of here's the utopia that we're all going to find the other side of the referendum."
Asked what hard questions are not being answered by the pro-independence camp, Sir Tom said: "There seems to be a scare story every day, so currency – what's the facts? Europe – what's the facts? Nato – what's the facts?"
While Sir Tom remains undecided, other prominent entrepreneurs appear to have chosen sides.
In February, travel trade tycoon John Boyle said he thought it would be an "economic and social catastrophe of epic proportions" to split from the UK.
A Better Together spokesman said: "We welcome Sir Tom's comments. We will be spending every day between now and the referendum promoting the many positive reasons why we are better and stronger together with the rest of the UK."
A Yes Scotland spokesman said: " Sir Tom is absolutely right in demanding straight answers to straight questions. We believe that Scotland should be run by a government that its own people vote for – not a cobbled-together coalition that Scottish voters never wanted.
"Yes Scotland will work very hard over the coming months to provide Sir Tom, and everyone else in Scotland, with the answers to the questions that will convince them that the only way forward is to vote Yes."