Hi WZ,
The diving in Oman at the moment is as good as it gets! As Sanddude said the ODC is a great place but book early to check availability! You might also like to try Global Scuba at the Aviation Club (SEEB). The Damaniyats are great at the moment - 30 meter vis and the chance to swim with a whale shark
If you are venturing to Salalah I can hook you up with the Extra Divers here. The beach diving is great and they have just aquired a very big boat! The quantity and variety of fish is truely stunning!
PM me if you need anymore info.
Regards
G030