OK, had to go to my backup memory and she is much better than me when it comes to remembering details but got some of the answers.

We used Ocean Divers (Key Largo) on one trip, they were recommended to us and were the guys who really helped us out. While we were out on one dive with them, they called other dive shops on our behalf to get us the kind of diving we were looking for. We also used Florida Scuba Diving (Key West) also but the shop was up for sale at the time, so I'm not sure where they stand right now, they were also good when we used them.

As I said, Speigel Grove was excellent, Cayman Salvager was another good wreck, as was the Adolphus Busch. You might take a look at http://www.divespots.com/scuba/home.page
as that site seems to give a lot of useful info about sites in the area.
Enjoy your trip.