If you have not done so already, you can download TouchCopy from here.
Many users need to do this exactly when they buy a new computer and they wish to transfer their iTunes library from the old computer to the new one. You can do this in four simple steps:
1. Ensure that your iPod/iPhone is loaded up with all your iTunes songs, videos and other content by syncing your device to iTunes on your old computer.
2. Download TouchCopy and install it on your new computer.
3. Ensure that iTunes is closed before connecting your iPod. Then start TouchCopy and connect your iPod. TouchCopy will have fixed your iTunes preferences so that iTunes will not sync music or video with your iPod while TouchCopy is running. These changes are restored when you quit TouchCopy.
4. Use TouchCopy to copy all your iPod content to your new computer hard drive or straight into iTunes. The details on how to use TouchCopy are provided in our TouchCopy tutorial.
TouchCopy will work just as easily if you're moving from a PC to a new PC or from a PC to a Mac.
If you've got a Mac formatted iPod that you're trying to use on a PC please see here for more info.
If you cannot fit your entire iTunes content on your iPod, you may need to load your iTunes content onto your iPod in smaller groups and copy it that way.