Restoring iTunes Music: Downloading past purchases from App Store, iBookstore, and iTunes Store
Restoring Non-iTunes Music (CDs or Third-Party): How to use your iPod to move your music to a new computer (may also work on older computers)
To locate your iTunes music/non-iTunes music:
- Windows XP: C:\Documents and Settings\username\My Documents\My Music\
- Windows Vista: C:\Users\username\Music\
- Windows 7: C:\Users\username\My Music\
- Windows 8: C:\Users\username\My Music\
Hope this helps. Good luck.