itunes [OS X] Copying MP3s (and everything else) from iPhone to music library

[whitebread]

I have an iPhone which I setup using my Acer laptop. I had all my music on the Acer laptop (which I originally downloaded from my "cloud"-based FTP backup to my hard-drive). I, like an idiot, returned the Acer laptop without making a back-up of my MP3s (I figured since they are still accessible via FTP that I can just re-download them if needed). I bought a Macbook with OS X on it.

My question is: how can I back everything up from my iPhone without wiping everything? I can live with re-downloading all the MP3s from my FTP server BUT I am concerned that if I sync the iPhone with my new computer that all my contacts/etc will be erased. I already went into iTunes and right-clicked and clicked both "Back Up" and "Transfer Purchases". What all did that back-up?

Thanks!

[Axel]

I also wouldn't mind an answer to this. There must be a way. My girlfriends little cousin just got himself a new laptop and god knows where whatever laptop/computer he was syncing with before is. It'd be nice to just copy his music/apps/films etc. to his new laptop and then I can teach him how to use it properly.

[Axel]

I just found this: http://thelittleappfactory.com/irip/index_irip1.php