Most of my diving has been off Key Largo through Atlantis Dive Center,
http://www.captainslate.com/ Slate does run larger head boats but I like his operation. We met in our dive instructors course in 1976! He stayed in instruction, I got out. If you are a fairly experienced diver the Speigel Grove is a nice dive, as is the Duane. You can find videos on all these wrecks on here through key word searches.
There are many dive operations throughout the Keys, some 6 pack (passenger) operations too. As far as Key West, if you are a fairly experienced diver you should consider diving the Vandenberg. It is in 140 ft., is massive but real interesting. In Key West you could contact
http://www.subtropic.com/ . There is a post on Keys diving operations that you may want to checkout at:
http://www.scubaboard.com/forums/flo...eys-guide.html If you have questions, ask them as I may know the answers or where to send you. Been diving down there since 1971 but most of that off Key Largo again. Have fun down there.