Griefcom

There are a ton of good reasons to join SFWA if you write Science Fiction or Fantasy.  There is prestige.  There is fame.  And there is the Griefcom. Griefcom is who you can go to when something is going really wrong in the business of publishing and normal channels aren't fixing it.  You must be a member of the SFWA to use their service but they can help negotiate issues of non-payment, revision of rights, or abusive contracts.  I don't know if RWA or MWA have similar programs as well but I highly recommend checking out the groups for your genre.