ratt,
a good source for florida is this
go to
www.myflorida.comhook onto the dept of agriculture
from there go to county fairs
another thing that you will want to look into is the dept of professional and business regulation.
they are the ones who will approve your rig and that will allow you to sell legally (and i have for darned sure had it up to my eyes with illegals!!!)
flea markets in my area are a no go since they have their own food and won't let you compete with them.
farmers markets are good but you will need your mfd and at least 1 mill in liability in my area at least
to do the major events like the florida folk festival you will need to submit a portfolio for their review and if you run on generators yours will have to meet their requirements.
things like bike week be prepared to pay upwards of 10k for the 7 days for a good location. the prime ones go even higher.
from talking to people in new york state and other states florida has about the toughest food regulations
hope this helps some
jack
ps. or you can risk it and do it illegal. civil fine is over 1k/day of operation but i forget what the criminal penalty is