well the term Naso is used to as an in general. there are if memory serves me correct 16 sub species of Naso's with the one's in the hobby falling under Naso lituratus. I'm sure all of them come from the Indo-Pacific (Hawaii, Indian Ocean, and the Red Sea) with most being imported from the Red Sea with Hawaii in second place. the color doesn't really dictate what location they came from. also not all males will have streamers.
If your lucky enough to get to see a Unicornfish in your LFS it's a Naso as well.
hth
kc