The AAP’s email listserv is administered by the University of Hawaii.
You can send an email to all subscribers at firstname.lastname@example.org.
If you want to register a new email address, so that you can receive AAP email and send messages to others on the list, you have a couple of options. You can email Dave Mason at email@example.com and ask him to add your email address to the list. Or, if you like to do things for yourself, you can follow the directions at http://www.hawaii.edu/askus/1099#1101