Please be very certain you are entering the correct email address. We get the occasional spammer trying to create accounts using bogus email addresses, so the process of authorizing new accounts requires that an email be sent to a valid account. That email will contain a link to finish the authorization process.
If for some reason you do not receive the authorization email (the subject will begin with "Account details for") within a few hours, please first check your email's spam folder and if it isn't there then contact the webmaster.