08 Jun 10 2:24 pm
This happened to me a few months ago. For the most part, this isn't really a big deal as long as your original articles on your site are already indexed.
In my case, they weren't. So I sent an e-mail to the guy that owned the offending trashy celebrity gossip blog. He took them down quickly.
If he doesn't take them down, you can always go on to hit him where it hurts:
Contact his hosting company and tell them that they are hosting plagiarized work
Contact the hosting company's bandwidth provider and tell them that they are providing bandwidth for a hosting company that is hosting plagiarized work.
Contact the advertisers on his website (Google Adsense, Clickbank, individual merchants, etc), and tell them that he is using plagiarized content to promote their products or services.
Contact Google, Yahoo, Bing, etc. and tell them that the website has plagiarized content and get them to deindex the site.
Find any friends' blogs or client lists on the site and e-mail these people that their friend or consultant is violating copyright laws and politely suggest that they terminate any business relationship with him in order to preserve the integrity of their own brand.
But, for the most part, this usually isn't a battle that's worth fighting. If you're petty (like me), it can be fun to exact swift and brutal revenge, though.
Have fun :)