I stopped sending my publishers and lawyer after all the pond scum providing free downloads of my work on the internet because:
• It’s free publicity
• I don’t want people who would steal things as my clients in any case
• The people who place them there, run the site, and download them are pathetic
Most of these sites originate in Eastern Europe or some other area I’d rather not be in any case. Don’t get all exercised when you find (or suspect) that someone has taken your “stuff.” Unless it’s egregious (a plagiarized book) it usually won’t hurt you.
I’ve also found that it’s people with weak brands who complain that their brand is being hurt, and it’s people with little business who complain that someone is stealing their business. Focus on building your own business to the point where the thieves are merely gnats on the windshield. Then hit the wipers….