yes, it is frustrating and there is not much you can do. I would not spend money and energy to follow up this matter, but I would send an email and ask him to stop this and that he is violating your copyright. You might mention that you will tell google about it and that your page has been indexed first and that this will be sufficient proof. This might frighten this person and he might remove the content.
You should put a
copyscape image on your homepage. This might frighten some people and stop them to copy. You place a little widget (code snippet) at the bottom of your homepage. You get that here at
http://www.copyscape.com/
I have done it too. It looks frightening and it is free.
By the way I love your site.