My Itunes has just over 3k songs, not that impressive but I'm adding to it everyday and it gets me by. I listen to a lot of stuff..
Anywhere from Lil Wayne to Hollywood Undead to Linkin Park to Tool to Billy Joel's Piano Man. It's very diverse, I like a lot of different music. I'm not a fan of country at all, and I don't listen to much sadder-sounding music. I like music that has a nice beat, and I love bass, hence a lot of hip/hop and stuff. But I also gotta jam out to my hard rock haha. It all depends on my mood.
Also, I like pandora.com it's pretty awesome. Don't leave it on all night though if you want it for free because you get so many hours of free radio time within a month. I ran out of time when I was first listening to it and had like two weeks left til the next month lol.