If it's just tracks for your own CD collection, then look on the web for a free programme (advertised in the missing manuals books) that lets you load things from your ipod into a computer. But if you can transfer the contents of the old HD to the new one, that's better and safer. And it should be possible if it's only the screen that went. Mac help pages can guide you through the steps if you have the right cable.

If you have tracks purchased *from* itunes store, then you will need to register your new machine to the itunes account, otherwise those tracks won't be authorized for it.