As far as I know, accounts aren't able to be canceled.
If you want to start over, simply make a new account with a new email address for the user name.
Although, to me at least, I'd rather fix the current issue rather than create a new account, so what link isn't working for you? the link to resend your password to the email address that the account was set up to use? Have you tried checking to see if it got blocked by an email spam filter?
