My sister lives in Florida and I miss her so much I have to go see her! Don't tell me if its a bad idea I don't care, how many days will it take are there any special trails?
Wanna go to Florida on a bicycle huh? Well, it sure is doable, and done right, will be a lot of fun. 'Course, if you not 18 yet, or mature enough, well......
Anyway, check out the link for loads of information on bike touring. I'm guessing it'll take about 3-4 weeks, and you might find a trail or two along the way, but mostly it'll be on highways.
Not to discourage you, but it's cheaper to fly to Florida than to ride a bike. And much cheaper on the bus.