I usually listen to the "Brand New Music" list of Filtr and "New Music" list of Digster on Spotify, brings up nicely a full list of songs that has songs that go viral like a month or two later.
Most radio stations now (with the exception of gems like KEXP) are corporate owned and play the same old thing. Pandora is great but it lacks the spontaneity of a DJ (I find I get tired of the same sound after a while). Spotify is good but it's hard to know what to search for (if you're looking for new stuff). Going out and seeing live music is great but there's a limit to how many shows you can see. Many live DJs are awful. Your friends might have different tastes or be into slightly different things at that moment. Blogs like Pitchfork can be great at times but it sometimes seems like they're trying to choose hipster, esoteric, or wacky(imo) music.