Well most people here (im assuming) listen to their music on cd by the album, since thats the way most metal is meant to be enjoyed anyhow. I cant stand streaming since it is LQ; I will only check out new music by streaming it, otherwise ill wait until I get the entire album. I find plenty of new music by checking out new releases and reading blogs and forums (this one in particular).
I have a last.fm account that I use mostly for keeping track of what I listen to, and sometimes i'll find the occasional band that I missed in the past that I should have already been listening to - count me for using lastfm for the occasional new find. Since I explore primarily metal genres, Pandora doesnt have enough coverage of bands who are on the less commercial side for me to find many new albums - ive heard of most of their recommendations already. So for me Lastfm is much more effective for finding new music. Ill always choose what I want to listen to, so radio station sites are pointless. Sometimes ill put my digital library (since I convert all my music to mp3/FLAC) on shuffle if I really cant decide...