I have the names of a few really nice dive sites, but I have no idea as to their exact location (Lat/Long) or in most cases what island they are near.
Austin Smith Wreck: It has a robust local population of Caribbean Reef Sharks, including one named "Finnegan" who is easily identified because he is missing his dorsal fin. I have heard that there is also a Goliath Grouper who calls the Austin Smith home. If you enjoy photography, the Nassau Groupers are very friendly and will allow you to get very close to take a photo.
Cracked Coral Head: This is a site with a little of everything. It has a sandy bottom at (IIRC) about 60' with a huge coral head in the middle of it. There is also a wall that drops off into the abyss. The huge coral head is a macro photographer's dream with Christmas Tree Worms and Feather Dusters blanketing it. This site also has a healthy reef shark population.
The Washing Machine: This is a drift dive that is extremely dependent on the tides. It is a dive in which you will tumble and the alarms on your Dive Computer will almost certainly go off.
Dog Rocks / The Cathedral: The Cathedral is actually a "swim thru" at Dog Rocks. It starts off as a normal swim thru, and then opens up into a majestic "cathedral like" room.
James Bond Wrecks: (Near Nassau) The Vulcan Bomber from "Thunderball" and the "Tears of Allah" from "Never say Never" lie right beside each other. Obviously, the Royal Air Force would not let the movie studio crash a real Vulcan bomber in the water off Nassau, so the studio built a full size mock up out of canvas stretched over an ABS skeleton. Now, the canvas is long gone, but the ABS frame is covered in sponges and coral. Right beside it (about 30 ft away) is the boat that was used as the Tears of Allah.
The Ray of Hope & Bahamas Mama: (Near Nassau) The Ray of Hope is a Freighter and the Bahama Mama are two shipwreck that are very near Nassau. Much like the James Bond Wrecks, these two are right beside each other. The Bahama Mama is pretty beat up, and not much left of her, but the last time I dove there, the Ray of Hope was pretty much intact. This site also has a healthy population of reef sharks and nurse sharks.
Sorry that I couldn't give you the locations of these sites, but I hope that the info I was able to give gets you pointed in the right direction.