iPod/iTunes Transfer Problem

I just bought the MacBook Pro and I wanted to sync all of the songs from my iPod with my new mac. I plugged it in and it only gave me two options: either erase and sync with my new iTunes library which is empty, or transfer purchased songs which is only about 600 of my total 3300 that I want to transfer.
Is there a convenient way in which to transfer "all" of my songs from my other computer and not just the purchased ones?

Do you have the tunes burned to discs? The easiest way is to burn them onto DVD's on the old computer and then drag them onto the new computer's iTunes.
You will have to sync with a new library though.
If everything is on your iPod there are programs that will transfer from it, but you need to pay for them.