Are you talking about books to develop yourself as a photographer or books about photographers?
I tend not to buy self help books because a lot of the information I need I find out in the internet these days, but, there are a lot of good books about photographers and written by photographers.
I'd recommend the following...
The Photographer's Eye by John Szarkowski
On Photography by Susan Sontag
Why Photography Matters as Art as Never Before by Michael Fried
Robert Frank's The Americans
In England by Don McCullin