Music from iPod to iTunes

OK I just got the 80 gig 5.5 gen iPod, NOW I loaded it up with my iTunes library from my computer and all that. Then I gave it to a friend and he loaded his music onto it from his iTunes off his computer. My question is can I go into the iPod and go through the music he loaded and rework the playlists and/or put the songs onto my computer that he loaded onto my iPod?

Don't steal music.. go buy it.