I'll give you two that I've enjoyed. The first is "On Photography" by Susan Sontag. This is a fairly philosophical book about photography, and photographs. A lot of people don't like it because she is not a photographer, and the book contains no photos. But she has been a close friend to Annie Leibovitz for many years, so I assume she has some knowledge of photography. This can be a kind of dry read, but I still liked most of it mainly because she is NOT a photographer. Published in 1977 originally I believe.
The other is "talking pictures" by Marvin Heiferman and Carol Kismaric. This is an unusual book I came across a few years ago, published in 1994, that has people from all walks of life talking about photographs they like. Most are famous, or at least know for something, such as Diane Keaton, Dennis Hopper, and Rosa Parks. Their choices and comments are not necessarily a critique, but their opinions and views on the photos they choose and just photography in general, are interesting.
There are many books to choose from in this vein, but I thought of these off the top of my head, and like them because they were written before digital, when it was all about film.