I used to live in the Orlando area but have been gone too long and things (buildings/houses) have grown up to fast, in too many places, for me to give you any field herping site recommendations.
If you get out near Disney World there's a small serpentarium that's decent. Reptile World Serpentarium, in St. Cloud, FL. It's basically a private collection of mostly venomous snakes. The owner, Mr. Van Horn, extracts venom for researchers, etc..., and does 2 short shows a day.
Keep in mind that it's nothing extravagant, but it's decent. I went there for the first time last week and it was worth the 45 minute drive & $6 entry fee to me. I got a chance to talk to the owner after one of his shows and we had a great conversation on relocating rattlesnakes.
He's got 2 Eastern Diamondback/Canebrake crosses that I thought were absoultely gorgeous. He's also got several other U.S. native rattlers, cobras, gaboon, and a few more. About 30 or so snakes in total on display, with a few gators, iguanas, water turtles.
Your best bet for seeing most of the things you want to see in captivity might be further south, in south FL (Miami, etc...) The Miami Serpentarium (Bill Haast) used to be nice but I've not heard anything about it in years.
Here's a pic of one of the cobras at Reptile World Serpentarium showing off behind my son's back.


Here's a pic of the Eastern Diamondback/Canebrake crosses.

Have fun!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American