As an avid collector of popular music as well as independent 'rookie-art,' i can confidently say that this is THE place to start and probably place to end your collection of music.
Why I say start? Well the staff at Carpenter can help reccomend you to artists you otherwise may or maynot know of. I know they helped me expand my collection greatly.
Moreover, they buy back music! Albeit at a discount, Carpneter will go on to pay 65% of an album's current market value for a used CD, Cassette, or Record in playable condition.
Huge selection. Smart doods. Great plce to loiter when you're bored. Enjoy.