Hey...
Can't give you any specific info. on the lakes around Orlando, but I do know there are several. Orlando isn't much of a drive to Daytona, if you wanted to sail in the ocean.

In the St Pete area, you could launch in Gulf Port (basically South St Pete), they have active catsailing in the bay down there. I'm sure that when the sailors from that area see your post, information will follow.

North of St Pete, we sail out od Dunedin Causeway. Nice launching beach, and you can either sail in the bay or hit the pass and go out in the Gulf. Numerous Tornado teams are training here at this time. Let me know if I can be of any help.
Dave