You actually can't. You can only listen to radio stations unless you're scrobbling music that you actually own or pirated (though I am not recommending piracy by any means), sorry. Once you have scrobbled the music and added it to your library, though, you can listen to all the music you've added to it on your own personal radio station. It's for fair use, but you'll probably get used to it. You can find a lot of new artists and songs from the radio stations, too. Anyway, I hope this helped you with your problem.