If you have a cover image, it can be magically attached to a realistic picture of one book or a stack of books at http://www.myecovermaker.com/
You can choose from a huge selection of book types, and even CD-ROMs, loose-leaf
notebooks, iPads and multimedia packages. Some pictures are freebies. Some other styles (like the one shown) have to be paid for with an inexpensive membership ($9 per month, or $90 per year). The service is extremely easy to use, and an image takes less than a minute to render and download.