Hi:
the main reason why your not seeing captive bred angels and tangs is becuz they're aren't any(many).
Clowns bred readily in the home aquarium, and fish hatchery. They are plentiful becuz theres a huge market for them. Unfortunately Angels/tangs, don't do what clowns do. Tangs for sure they require adult fish (which are often huge) large swimming areas. Not very condusive to mass production.
I have only seen captive raised maculatus angels, and have read about a group in Japan which was succesful w/ large form angels. Additionally the waikki aquarium announced the breeding of a centropyge angel in their catpive care.
As far as tangs. NADA.
You might try FFExpress.com as they have a captive raised section. Essentially fishing trawlers capture tons of larval fish as by-catches to regular fishing. Some places purchase this by-catch and grow it out. These larvae then are sold a captive raised fish.
I believe they have a few tangs
HTH
C-Quest grows out Hippo tangs, rock beautys, etc. that they snag out of the ocean as plankton and grow out at their facility. They're very hardy, you have to be very skilled at killing fish to lose them.
If only they could do that with mandarins, moorish idols, coralivorous butterflys...