A vehicle is recommended for this cache as the final is about a mile from the first waypoint.
The coordinates will lead you to Austin's own medieval castle. After admiring from the car the unusual (or shall I say "Keep Austin Weird") structure, write the down the house number of the castle: ABCDE.
The coordinates of the final are:
You should be able to find a good parking spot accross from the final
PS: The house was actually featured on episode 106 of HGTV's show "What's up with that house?"
Update 7-4-2010: New container. It is now lower and you will have to come out of the car to get it. One step required. sorry!
Update 1-7-2011: New container, the final has moved slightly. Same as before, you will need one step out of you car.
12/26/2011 Update New container, you will need to park the car 100ft from the cache. Title, Formula, Hint updated.