One of the best uses for stock photography is when you can find that perfect image that allows you to incorporate your elements (text, logos, other images) into it. That's called copy space, and it's something I try to build into my images whenever possible. A lot of my photos come ready-to-use, with an area already set up for your headline or logo.
Below is a random smattering of some of my favorite copy space images. You can click here to see all the copy space images in my iStockphoto portfolio.