Model A1059 or A1099 / 20, 40, or 60 GB hard drive / touch sensitive click wheel iPod 4th Generation or Photo troubleshooting, repair, and service manuals.
XPS Replacement Battery for Apple iPod 4th Generation, iPod Photo, iPod U2 20GB Color Display MA1 PN 616-0183, 616-0206, 616-0215 : Electronics
iPod Nano 4th Generation Repair - iFixit
iPod Touch 4th Generation Home Button Replacement - iFixit Repair Guide
iPod Touch 4th Generation Teardown - iFixit
iPod 4th Generation or Photo Logic Board Replacement - iFixit Repair Guide
iPod Touch 4th Generation Teardown - iFixit
Simple guide for open and repair of Ipod Classic 4th generation hard drive
Apple iPOD 4th Generation Media Player Replacement Battery
Apple iPod Touch 4th Generation (2010) Teardown