I'm assuming this is on a Windows computer?
All the music on a Windows formatted iPod is stored in a hidden folder on the iPod. You need to tell the iPod to be running in "disk mode" by holding down some keys: http://support.apple.com/kb/ht1363
Then, connect the iPod and it should appear just like a very big USB key. In the exlorer window, click on the Tools menu and go to the Folder Options menu. In the dialog box that appears, click on the View tab and tick "Show hidden files folders and drives". Click OK and you should now be able to see that some extra folders have appeared on the Ipod disk…
Now, I can't absolutely remember the name of the hidden folder you need to look in but have a browse around – you'll find it…
Copy them to your computer…