I saw both Faiths+Pantheons and Stronghold builder's guide at my local gaming/comic store. I've actually found more stuff in Ames IA than in St. Louis.
Somehow, the building prices WotC has been using seem wrong. They all seem way too expensive from a mechanics oint of view. How much utility do you think an adventurer gains from a castle worth 500k versus +10 armor, a +7 sword, Rod of Security, Helm of Teleportation, ring of sustenance, a cloak of resistence +5?
By the time you can afford a big castle, your enemies won't be impressed either.
It just seems the prices were inflated to make things more expensive for the PCS. I can see spend some gold on a castle that serves as plot hook at best and point of vulnerability at worst for the coolness of it, but I can't a character facing 20th level threats with 1/2 of his resources sunk into an expensive stone bull's eye.