Before attempting to sell photos through a stock photography company, you should gather together as many different images as you can. Nearly any type of image -- a person, an animal, a landscape or a building -- may have some stock photography potential. Some stock photography companies only deal with photographers when they have a large amount and variety of images. Stock photos most often come from a photographer's personal collection, previous assignments or photography taken with stock photography in mind. It pays to take some time to generate a lot of images before entering the stock photography market.