I have Thunderbird. I used to be able to "blacklist" certain addresses but that function seems to have been replaced by another version:

Under Tools | Message Filters I can create a filter that will automatically treat all messages from a particular address in a particular way: for instance, move them to a junk folder or delete them.

Some mailing lists include an "unsubscribe" link at the end of every message. I take it yours doesn't?