We have set up a private Google Groups mail list and will rely solely on that for Troop e-mail broadcasts and discussions.
There are two ways to join:
Send an email to the webmaster and they will manually add you to the list. Contact them at email@example.com
Visit the closed group, login with your Google account and request access to the group. Visit the group by clicking here
Changing an address? Unless you are using a Google Account and change it in your profile, there is no way to do it. You will need to un-subscribe your old e-mail address and then subscribe again using your new one.