CAcert Incorporated is a registered association in Australia, which operates the CAcert.org service.
Rules
http://www.cacert.org/docs/CAcert_Rules.pdf
Membership
If you want to become a new member, please read the rules, afterwards fill out this form: http://www.cacert.at/svn/sourcerer/CAcert/CAcert-Association-Membership-Application-Form.pdf
You can pay your yearly membership fee through Paymate: https://www.paymate.com.au/PayMate/PaymateExpress?mid=cacert&ref=CAcert-Inc_Membership-fee
Board
http://www.cacert.org/index.php?id=8