The eight sites listed below offer huge libraries of free royalty photos you can use in your projects - and most have no restrictions on the use of the photos, except that you can not sell the photos in a collection of photos for reuse.
The Commons on Flicker - a great place to find public domain images from archiving institutions around the world. According to the
http://www.flickr.com/commons/usage/, all of the images are available for reuse without any copyright restrictions.
Stock.xchng - Almost 400,000 royalty freem images, managed by Getty Images. Searchable and downloadable. Find full terms of use at
http://www.sxc.hu/info.phtml?f=help&s=7_2 MorgueFile - A huge collection of professionally shot photos. You are free to adapt the images, free to use for commercial purposes, no attribution required. Find terms of use at
http://www.morguefile.com/license/morguefile/ Photos8 - More than 10,000 professionally shot and searchable stock photos, offered royalty free. Attribution required. Find terms of use at
http://www.photos8.com/license.html StockVault - Thousands of professionally shot stock photos, with no commercial use restrictions. Search by keyword and category. Find terms of use at
http://www.stockvault.net/licensing.php PhotoRack - Thousands of professionally shot stock photos, with no commercial use restrictions. Terms of Use: All photos at PhotoRack are Free to use for personal and commercial projects. No limitations.
Wikimedia Commons - more than 7 million freely usable photos and video files, searchable by keyword and category. Most photos submitted by individuals, and some photos require attribution. Terms of use shown with each photo.
Photogen - thousands of professionally shot stock photos searchable by category. Registered users can download and use Photogen stock photos FREE, both for commercial and personal projects. Registration is free.