We've made quite a few trips, and by far the best underwater destination is New Guinea in our opinion. I think you'll understand why from the pictures below. In general I suggest travelosity or expidia for airline, hotel, car, and other reservations. There's even pointers to cheap cruises and cheap air fare. (FYI, if you want to experience the same types of luxury bedding as the top hotels try this discount bedding page. They have 800 thread count sheets under $100 and more.)
eel in coral Eel sticking out of the coral
mantis shrimp The mantis shrimp is pretty good sized and can take off a finger, or break an aquarium
nudibrach on red sponge This small colorful animal really was on this sponge
soft coral and fish landscape A landscape picture to give you an idea of how things look
turtle over coral A turtle, don't know which kind
blue ribbon eel A blue ribbon eel. Common in New Guinea, not seen in too many other places.
chronid fish This little fish likes to dart around, lucky shot!