if your IPod touch is not connected to itunes, please try the ff:
Check the iPod touch Display
-- When you connect iPod touch to your computer, the iPod touch should display an image or message on the display
-- If you do not see any image, check some basic troubleshooting here: http://support.apple.com/kb/HT1737
-- If you see a message on the screen, this indicates that the iPod touch does not have sufficient battery charge to operate and will need to be charged for several minutes before it can be recognized in iTunes.
Verify Windows PC System Requirements
--iPod touch requires iTunes 7.4 or later
Check USB Connections
-- iPod touch requires USB 2.0 to function properly
-- Try connecting iPod touch to a different USB port, preferably a port that is built-in to the computer instead of an external USB hub. Connecting iPod touch to your keyboard's USB ports is not recommended.
Restart your PC
-- In some cases, your computer's USB ports may become temporarily disabled or you may experience other software related issues. Restarting your PC is an easy troubleshooting step that may resolve this issue.
Verify iPod touch Driver/Service Installation
-- iPod touch requires two important pieces of software to operate properly on Windows. First, the driver must be installed; for iPod touch the driver is USBAAPL.SYS. Second, Apple Mobile Device Support must be installed as a Windows Service.