The Best Search Tool for the Phoenix Area is FLEXMLS. 

While less than 5% of agents provide open access to the FLEXMLS system, researching real estate is fun and relatively easy with a little effort. Complete access to the FLEXMLS system is available to anyone through this web site. All information is kept strictly confidential and there is no obligation. FLEXMLS is very different from most consumer tools which often use outdated information resulting in wasted time looking at properties which simply are no longer available or missing out on hot new properties. Real time FLEXMLS data is exactly the same as the data available to area agents. The moment a property comes on the market or has a status change, you will be made aware of it. You can set up automated emails if there are any changes in the areas or properties you are interested in. You control the flow of data and may know about new properties or changes before I can inform you about them!