How to remove your Gmail account
Immediate link for Gmail. Beware: there is a more general link for unsubscribing from all kinds of Google services. See also our ‘Google’ entry and https://www.google.com/support/accounts/bin/answer.py?answer=32046
Direct removal link: https://www.google.com/accounts/DeleteCaribouService
Helpful Trick: Removing online data
Publicly visible text/images often aren’t properly removed even when you succeed in removing an account. Try editing or removing them manually before removing the account itself. If you’re unsure what happens to your tracks: this can be found mostly in the Terms of Service/Privacy Policy; otherwise you can always contact Gmail and ask personally. By the way, removal requests don’t necessarily mean your data will actually be removed (e.g. due to legal obligations).