John,
I have about 5 sources I will share the best of the bunch soon. There are some data bases that are local to a state that are the best in terms of loaded with information and easy compared to the big ones it seems and cheaper. I am still playing with Propstream and have had Property Shark. I will have this in the next class.
Once you import your data in to excel or another spreadsheet it gets easier. But again driving and knowing the property after you identify some data potential winners from the data is really good and helps you focus.