Probably several good choices. Even if you buy locally from your LFS, have you 'window shopped' LiveAquaria .com and Saltwater Fish .com to see recommended tank sizes?
Depends on the size and type of fish, but you could have around 4-7 fish in a 29g, and 6-9 in a 40 gal.
You have a ton options for fish so i would just go on live aquaria, pick a few, then come back and see if they will be okay. I think a dwarf angel, couple of clowns, a blenny, and a pistol shrimp pair would be some good options for both.