The guy in question here may be a Joseph Stack.
This plan is registered to a Joseph Stack...
look where the last flight plan ended....Georgetown, TX.
Now, I am still a bit confused here....it could be Stack was the victim of the theft and is not the person who flew the plane into the building here.
But, the plane is tied to him:
http://flightaware.com/live/flight/N2889D
And post # 520 is also STACK.
But, the only Joseph A Stack that is in the pilot registry has rotorcraft ratings. He has no airplane ratings. But, there's also no address in the public records.
I suspect this is a stolen plane.