Of course I buy books and photographs by other photographers.
First of all, I bought a photograph by the famous photographer Sergei Maksimishin. (those you respect) I also bought books by Dmitry Markov. Many of my friends are photographers and collect cool books by photographers, both super famous and young. For me, this is as important as a collection of any art, painting or graphics. In my house, all the walls were hung with paintings.