Try slowly turning the volume down all the way until it goes to vibrate. I'm not familiar with the ipod, but lots of devices work that way so it's worth a try.
After looking mine over really quickly, it does not have a vibration setting of any kind. Reason being is that it's too thin to have a vibration mechanism.
yeah like courtney said the ipod touch doesn't have a vibration mode:) i have an ipod touch
I'm pretty sure the iPod touch doesn't have a vibration mode.