You can always get the best of the best and download iTunes from apple.com - access their Music Store and you can get 30 second clips of insane amounts of artists.
Only drawback is that if you actually buy the song, they send it to you in a fucked up m4p format that took me a while to figure out..just break open the code in your Terminal and delete the security line.
Or..just burn the song onto a CD and then convert it to mp3. I just like the hot programming involved, haha. Okay. I'm done.