Hey I had a powerbook g4 and I upgraded to a macbook. The thing is that I have tons of music on my iPhone 3GS and when I try to sync the music to the macbook it tells me that the iphone is already synced with another computer and it tells me to erase and start from scratch. I want to know how I can transfer all the music from the phone to the macbook, so I have it there incase I loose anthing on the phone. Thanks in advance for all your help. Also I don't have the Powerbook I traded it for a macbook and cash, so I don't have a way of going back to the powerbook. All the info is on my 3GS. I have to find a way to get it from the phone to the macbook, so that all my music is on my itunes library in the macbook. Thanks.