I also live in the area and was curious as to what you can find out there. I've collected at Picnic Island in South Tampa and gotten a pretty cool Pistol Shrimp, Porcelain Crabs, Small Stone Crabs and some cool 1/2" ghost shrimps. I've also found plenty of White Clawed hermit crabs which do a great job of cleaning up and are pretty fun to watch. Also found some kind of snail that buries in the sand and crawls around the glass.
I've wanted to see what else is out there out in the gulf but wasn't sure where to look or what was the best technique to catch stuff. I did find this website which is pretty good in identifying specimens.
http://www.sms.si.edu/irlspec/Animals.htm