Lists other than fitforum and facforum are mantained by their own administrator. Many administrators have set up automatic methods to unsubscribe - often times e-mails from the list include this information.
If you wish to unsubscribe from a list and you do not see an automated method, you will need to contact the owner/administrator of the list.
If you do not know who the owner/administrator is, you can view this by searching for the list here or contact the Technology Support Center (email@example.com) and they can forward your unsubscribe request to the appropriate party. (Note that this method may not be as fast as contacting your list's administrator directly.)