There is not currently a book on Ralph Haver and everyone keeps telling me that I'm the one to write it
Maybe someday. I certainly have enough info for a whole book and can field most questions if you have anything in particular you're researching.
However, if you're looking for books that prominently feature his work try A Guide to the Architecture of Metro Phoenix by the Central Arizona AIA (out of print, available at some libraries) and the upcoming book Midcentury Marvels by Don Ryden/City of Phx. Publication date for Midcentury Marvels is any day now, I'll make sure you all know where to get it when its ready.
One of the more complete online resources is http://www.modernphoenix.net/haver/haverportfolio.htm
which was literally written by his firm. What I published here is just the tip of the iceberg of what I have available from their professional portfolios.
Additionally check out all the primary source info on him at http://www.modernphoenix.net/architects.htm
and the article I contributed on his work for Wikipedia.