These four links will give you the overview necessary to fully understand the Phoenix Arizona real estate market. The Lawrence Yun presentation is more of a national perspective. Did not know he went to Purdue University for his undergrad work. Probably long after I was there.
There is a huge amount of information here. Pace yourself.
Lawrence Yun with National Association of Realtors
Michael Orr with the Cromford Report
Fletcher Wilcox with Grand Canyon Title
ROI Properties October Newsletter