Is your iPhone or iPod not getting detected by iTunes?
If yes here is the way to get your device back to the iTunes.
iTunes is using two background services (Apple Mobile Device Service and iPod Service) while it is running. These services will be watching your USB ports and if an iPhone or iPod is connected they will detect those.
If your device is not getting detected first thing you need to do is to check the service statuses. It is always good to stop and restart the services using the Services in your machine.
To check the statuses first making sure iTunes is closed and your device is disconnected from USB ports then go to Start -> Control Panel -> Administrative Tools -> Services.
There you will find Apple Mobile Device Service and iPod Service.
Right click on each service and Restart (Better to Stop and Start) them.
Then start iTunes and connect your iPhone or iPod and the device will get detected again in iTunes.
If this fails you need to restart your machine and check again and if that also fails better try reinstalling iTunes with the latest version from Apple.
Arjuna's space 