Wikimedia Commons is an archive of Public Domain and Creative Commons images. Much like Wikipedia it is organized by historical subjects, and is collectively edited and maintained.
1. Go to the Wikimedia Commons (http://commons.wikimedia.org) and search for Walter Gropius, the founding director of the Bauhaus.
2. View several of the images, and notice beside the image description, at the bottom of the screen, that the images are either Public Domain or licensed Creative Commons.
3. Flickr is a photo sharing site that encourages the culture of sharing through many of its features, and many Flickr users license their photographs under Creative Commons. Go to Flickr (http://flickr.com), click on the magnifying glass at the top of the page and search for Bauhaus.
4. Select “Al Creative Commons” under the license menu, which is by default set to “Any license”.
Everything in your search will be CC licensed, though not all will allow derivative works (for example, using the image in a collage) or commercial use.