One common problem people have is finding the various emails the lists sends.

First, one trick that can be done to improve the chances of mail being delivered is to add the address the list uses to your address book:

• arlington@lists.arlingtonlist.org
• arlington-request@lists.arlingtonlist.org
• listgnome@ash.mailmanlists.us

Then you should check carefully for places your mail system might put the message where you don't expect them. These include folders like spam, junk, bulk, or other alternatives like that. GMail adds other places with its "alternate inboxes" across the top of its page, particularly Forum, or perhaps Social.

There is currently an issue with Yahoo (and AOL and Verizon that it runs) that they send back rejections for too many messages being sent to it, so members on these services tend to have problems, but the above might help.