It's been a while since I've set up such a list, but when I have, it creates several email addresses that show up in the Panel under Manage Email. Here's what it sent me a while back:
You can also make such adjustments via email by sending a message to:
with the word `help' in the subject or body (don't include the
quotes), and you will get back a message with instructions.
List specific commands (subscribe, who, etc) should be sent to the
*-request address for the particular list, e.g. for the 'mailman'
list, use 'mailman-request@...'.
Also, you should see much of this from the admin page: