I apologize if this has already been posted here or linked to but I think it is very helpful to many of us to take a quick peak at this tutorial:

http://support.envato.com/index.php?/Knowledgebase/Article/View/536/99/how-to-remove-illegal-results-from-google-web-search-and-other-google-services

I'm not sure if you have to be logged into your Envato account in order to see the tutorial but in any case: Google Webmaster Tools provides a link to make a DMCA request so that illegal links to your copyright protected content can be removed.