If your iPod can't connect to the iTunes store, check out this article for some additional troubleshooting steps:
If you haven't been able to connect to the iTunes Store:
- Make sure that your iOS software is up to date by connecting your iOS device to iTunes and clicking on Check for Update in your device's Summary page in iTunes.
- Check and verify that you are in range of a Wi-Fi router or base station. If you are on a 3G capable device, make sure that cellular data is turned on from Settings > General > Cellular.
Note: If connected to 3G, larger items may not download. You may need to connect to Wi-Fi to download apps, videos, and podcasts.
- Check to make sure you have an active internet connection. You can check the User Guide for your device for help with connecting to the internet.
- Check to make sure other devices (portable computers, for example) are able to connect to the Wi-Fi network and access the internet.
- Try resetting (turning off and then on again) your Wi-Fi router
- If the issue still persists see, iOS: Troubleshooting Wi-Fi networks and connections or iOS: Troubleshooting Wi-Fi networks and connections.
My iPod nano 5th gen suddenly quit showing up in Finder and on iTunes. The iPod would not stay connected. It seemed to connect, say it was connected, but still not show up in Finder or iTunes, then reboot after a few seconds of being connected. I tried changing cords, tried connecting to other macs, even tried connecting to an old Windows machine. It would simply not connect or show up on any system dashboard.
I finally came across this link which helped me fix the problem: http://support.apple.com/kb/HT1363
I followed the steps to put the iPod into "disk mode". This worked. I was able to successfully connect the iPod while in disk mode - it was recognized in iTunes. iTunes immediately reported that the iPod was potentially corrupted and needed to be restored. I happily clicked "restore", then resync'd my music and now everything is back to normal.
I hope this helps any one else who might have the same problem.