iPod transfer help please!

[wiper]

i moved, and took computer with me, with the entire itunes library. old roommate still has my ipod with all the songs on it.

how do we put the library from the ipod onto my old roommate's computer, so that it's on the new laptop??

i've heard you have to buy a disc or something..all i know is that if you plug in the ipod into the new itunes library, the ipod will update to the new itunes library, thus losing everything on the ipod...