This actually happen quite often. Consider following the advice in Updated procedure for reporting SCRAPERs (copied below):
tl;dr: Send all reports of SCRAPERs to us via the form on the contact us page, linked at the bottom of every page. Please include:
- the URL of the copied post
- the URL of the original post on SE
- for high-rankers, the search string you used (and the name of the search engine, if not Google)
- any other details you noticed and want to share, because you're awesome
(This is the end of the tl;dr section.)
I used to be the de facto curator of the two SCRAPER reporting posts here on Meta: one for attribution and another for ranking. The community was pretty good about using them, but like all list questions, they eventually turned into unmanageable messes that were hard to search. I've just saved all of the information posted there and deleted them.
The community team has been working on improving its internal process for SCRAPERs behind the scenes, and now that I've joined the staff, I'm going to be in charge of it. By funnelling everything through our usual support mechanisms, we can organize our own efforts better, and as a side effect, we won't be giving Google-juice to the very sites that are being called out for being naughty.
From the original announcement tweeted by Matt Cutts, head of Google's anti-spam team (at the time of this writing):
"If you see a scraper URL outranking the original source of content in Google, please tell us about it: http://bit.ly/scraperspamreport"