You will absolutely LOVE flying in the States!
No landing fees. No approach fees. Often no parking fees. Most airports open 24 hours (lights on a radio frequency). America really is the land of aviation opportunity.
The first respondent was absolutely right though - you MUST get your FAA licence sorted out to fly solo. This involves some paperwork, some money to our CAA (the FAA won't charge you!) and an appointment at the FSDO when you first arrive. It's absolutely no drama.
Why Florida? If you're open to persuasion - why not Arizona? You can do the Grand Canyon, the Hoover Dam, VEGAS! - plus loads of other stuff. Check out
www.shebleaviation.com. They were renting out 172's (inc. fuel) a couple of months ago for $79 an hour. With the exchange rate as it is - that's about £40!
You'll not be able to do any flight training requiring a visa at Sheble's because they can't issue the visa paperwork - but they can do you a check out (no visa required for that) and will rent you a decent plane to go play in.
Any questions - PM me!