but any notes on the architecture ofthe system and how you put it together would be cool.

I've been thinking of writing a detailed meditation or article about building the system, which was a lot of fun and also a real challenge. Right now I'm beginning work on version 2, which will have some new features.

Do you distribute your system? Is there a cost? What is the license? Is Alexander currently searchable by the public/is there a link to it?

Alexander is currently proprietary, but subscriptions are available via the Conjuring Arts Research Center. There aren't any plans to open-source the code right now, and much of the indexed content is under copyright and licensed to CARC, so it's not publically searchable. And since it all runs on a single 1U server which is on the verge of melting into a smoking heap of liquid metal, that probably wouldn't be a good idea anyway. :)