Ken, I don't know when for certain I would make the trip. It depends a lot on when I have the time and money to do so.
When I do go, the study of buildings isn't going to be the only thing I do either!
As for an outline book reference, that will take some work! I am not aware of any book on the subject in the English language, and I have searched hard for one.
The website Fachwerk.de is a good starting point. The also have a books list there on that site.
search for pics of Fachwerk, Fachwerkhaus, Riegelhaus, and 'Alemannische Fachwerk'