http://www.valhalco.com/index.php

Apparently the Home Depot and Lowe's don't carry it and that explains why I haven't seen it.   The idea of having to stain wood only ONCE seems too good to be true for Arizona.  Unfortunately, you can't use it over previously treated wood, so we'll have to wait for new construction to try it out.

$70.33 for 5 gallons at Amazon right now:

Check out the section on "Customers Who Bought This Item Also Bought" for other brands.  I didn't know there was that much available.