In the past I had access to corporate stock photo accounts and it was very easy to find images and test out various compositions. When you are in house or working on a shoe string that may not be an option. If you use stock photos from a commercial site, sometimes its not so easy to get someone to pay for them.
Wouldn't it be great to have thousands of high quality, free stock photos at your fingertips? Here's my list of royalty free, fee, high resolution, stock photos that don't suck.