The Art of the Photogravure. It is a serious guide to the history and technique of photogravure as well as extensive coverage of artists (historic and contempoary) using this process in their work.
The artist I featured above is teaching a photogravure workshop with CPW in the summer 2009. He is incredible! You can check out what The Art of Photogravure has to say about him by going here. Or you can check out his personal website here.