If you don't want to cancel, but you want to change the credit card number you're using, or the expiry date go here.
If you want a password reminder, then go here.
If you want to send a secure message to the webmaster go here.
If you joined via Verotel (then your username will be an eight digit number, and your password is a seven digit number), then to cancel you go here
You can cancel rebilling, which means that when your membership expires it will not be renewed. Or you can ask for me to bill you a certain number of times from now, and then cancel after that (for example, you might decide to join for one year and then be automatically cancelled, in which case for monthly memberships that would be 12 billings (for a membership which is billed quarterly, that would be four billings).