Lifehacker: Geek To Live: 6 ways to find reusable media.   Juicy Info and Links here.

http://www.bigfoto.com/   Bigfoto copyright is very simple. You have free use of all pictures if you provide a link to the bigfoto website.

http://www.freephotosbank.com/   Copyrighted, can be freely used for commercial and personal projects per terms of use on site. nice collection of photos.

http://www.office.microsoft.com/   Microsoft. The MotherLode.

http://pdphoto.org/   Public domain photos. Thousands. Free.

http://www.deniscarl.com/   Wonderful collection of creative commons photographs, including images of coyotes!

http://www.fromoldbooks.org/   Enormous collection of Public Domain images scanned from vintage books

http://www.photolib.noaa.gov/   The NOAA collection spans centuries of time and much of the natural world from the center of the Earth to the surface of the Sun. ...Most photographs are public domain. Although at present, no fee is charged for using the photos credit MUST be given to the National Oceanic and Atmospheric Administration/Department of Commerce unless otherwise instructed to give credit to the photographer or other source.

http://www.imageafter.com/   Image*After is a large online free photo collection. You can download and use any image or texture from their site and use it in your own work, either personal or commercial. They also have a newsletter with links to the latest images added to the collection.

http://www.sxc.hu/   Stock.XCHNG: free stock photo site

http://presentationzen.blogs.com/   list of where to find free and almost free stock photos

http://commons.wikimedia.org/   The Wikimedia Commons has a huge collection of free photos, including archived historical photos, well categorized and organized..

http://www.smileycat.com/   list of free and low cost photo sites

http://flickr.com/creativecommons/   Creative commons photos on flickr