For the most part, I find new music through a combination of YouTube and Spotify. I'm too cheap to pay for Spotify Premium, so after I've listened to a track 5 times, I can't listen to it via Spotify any more. Hence: YouTube. However, if YouTube fails to come up with the goods, I'll sometimes resort to using Grooveshark... but only when I can't find it through completely legitimate means and I don't want to actually buy the album/song in question from iTunes.