Last.fm
So, I recently started using Last.fm because our guest lecturer mentioned it as a way of finding new music, which I'd been wanting to do.
Last.fm is a site and a downloadable program that work together. One of the things I find particularly useful is that the site tracks the popularity of individual songs by particular artists through a downloadable program that does something called "scrobbling." Scrobbling is when the program + site keep track of what songs you are playing on your computer and collects the data so that you can see which artists you are actually listening to the most. It will also, if you browse through other members' profiles, give you a compatibility rating that indicates whether or not you might have similar taste in music. The program also has a streaming radio feature where you can type in a bunch of artists and songs by those artists or similar artists will play.
Last.fm makes recommendations through "scrobbling," but when you search on your own, you get results that are tagged by other users.
This website makes information useful and not overwhelming by organizing results hierarchically in terms of popularity so that it's easy to pick out the artists and songs that seem to be the most popular.
A competing website is Pandora, which is superior in the way that music is recommended to the user. They basically have music "experts" that analyze songs according to specific criteria rather than letting users tag things, which can sometimes get people results they don't expect or want (like the whole Barry Manilow as death metal thing).

