Quick MOSS tip-o-the-day:
If you need to retrieve the ID (GUID) of a Feature, for running STSADM commands, etc, there’s a quick and easy way to do this for features that are currently activated:
1. Go to your Site Settings, where your features are listed and you see the Activate/Deactivate buttons.
2. Press the Deactivate button (don’t worry, this goes to a confirmation page, so you’re not causing anything to happen yet)
3. While you’re on the confirmation page, take a look at your browser address bar – voila, your feature ID: