Google Image Search Implements CC License Filtering – Creative Commons
Today, Google officially launched the ability to filter search results using Creative Commons licenses inside their Image Search tool. It is now easy to restrict your Image Search results to find images which have been tagged with our licenses, so that you can find content from across the web that you can share, use, and even modify. Searches are also capable of returning content under other licenses, such as the GNU Free Documentation License, or images that are in the public domain.
To filter by CC search, go to Google’s advanced Image Search page and select the options you’d like in the “Usage rights” section. Your results will be restricted to images marked with CC licenses or other compatibly licensed photos.