I think the "retail" opportunities are pretty weak around there.
I've heard of a couple of large commercial distributors near Orlando--they sell to
larger accounts and sometimes allow cash sales. (e.g., McEwen or Cramer).
There are lots and lots of small mills around the state and folks literally working out
their backyards.
I'd suggest going to Woodfinder.com and seeing what shows up.
Then, look at Craigslist.org under "mat" (for materials) -- usually lots of folks selling wood that way.
Also, I've learned that tree surgeons can have good local wood for sale.
BG Sawmill up in Eustis should be worth visiting.
There's also a place called Kempfer's Sawmill in St. Cloud but I've don't know anything about it.