Although I moderate two lists through Egroups.com and am a member of many more, I am still learning the ins and outs of mailing lists and electronic newsletters.
Jakob Nielsen’s Mailing List Usability article is a good place to start for those wanting to learn the ropes first. And Vivian Neou has provided a great resource on mailing list products and hosting services. Check it out at http://catalog.com/vivian/.