Forum Moderators: mack
I'd suggest that you start by doing through appropriate categories at ODP, Zeal and Yahoo. There are probably loads of great sites that offer free newsletters. Just to be on the safe side, take web-based email to use for subscribing. Once you get a few you can pick and choose which to keep. Also check search engines - there are so many out there.
I must say though, that if you go back and read all through our Advertising Sales and Affiliate Programs [webmasterworld.com] forum, you'll find it more chock-full of great information than you could get in a years worth of newsletters for the topics that are covered. Some of those people are absolutely the best in the business, and they've shared their knowledge liberally and generously.