I did a screencast on this topic back in September, but I wish I had Amy Gahran's advice on the topic. She tells you how to do the search, gives you an example, and shares some pitfalls to avoid. I'm going to quote them here:
- Is the subject of the photo copyrighted? If the photo is of, say, a TV screen showing a newscast or a newspaper page showing a staff photo, then you still might be liable for copyright violation despite the terms of the CC license listed on Flickr or elsewhere.
- Does the Flickr user really have rights to the image? Unfortunately, many Flickr users post to their accounts images that they did not take and don't have permission to use. In that case, their CC license is invalid. If you're not sure, ask before using.
- Is the image genuine? Remember, any photo (even from allegedly reputable pro photojournalists) can be faked or altered. If you have doubts about authenticity, investigate before running the image.
- Protect yourself. Save or print the screen where you found the photo that shows the CC license notation. (Furl is a great way to keep such evidence.) That way, if the photographer later tries to revoke the CC license, you can show it was in effect on the date you published the photo.
She also suggests:
Whenever you use a CC-licensed photo that you find on Flickr or elsewhere, it's a good idea to leave a comment or send a note to the photographer thanking them and giving the link to where you ran it. That's more than just being polite -- it also can prevent criticism that you're exploiting unsuspecting amateurs. In photography, as elsewhere, appearances count.
Although some say that the spirit of the "by" is to eliminate the both of asking permission because it is given via the license. See Amy's coverage of the Lisa William's pressthink piece about the first newspaper chain to use the creative licensing. As was the buzz last night at the CC Birthday Party, Larry Lessig has done so much to inspire this shift from a culture of protection to a culture of sharing.