The purpose of Publish-L is to provide a forum for the exchange of ideas and information about publishing and marketing books and related materials.
The good news is, as a self-published author and reader of this blog, you have some very valuable stuff to share with the people on that list. You might even say you are a marketing expert. The other folks on that list will be drawn to you because of the advice and tactics you can share. Social Media is great, free publicity.
Just be sure to sign every email you write and discussion you post with information about your book, including a link to your webpage. After all, helping others is fun, but so is selling some books.
See you there.