We seem to get a lot of requests for people who didn't get the activation email. Here's a solution to re-request the activation email. If doing this doesn't seem to work, then you'll still have to use the contact us option.
Click this link and enter your email address (or the email address of the user you want to send activation codes too) and it should handle it.
Email Activation Codes - Cartographers' Guild
Robbie Powell - Site Admin