I have a database of over 11,000 individuals including virtually all American Riedesels born before 1980, large numbers of their ancestors, and many other related families from Wunderthausen. No one matches Ancestry.com for raw data, but I have access to multiple transcriptions from the original church records for Wunderthausen, have received (and contributed to) the Wittgenstein historical magazine for over 25 years, and have good connections to many researchers over there who have been immensely helpful.
I have a good knowledge of the local history and culture, and of the German language. All of this helps make better sense of the raw in which genealogists swim these days.
This site uses GED4WEB software to create the files available here.
Click here to access the genealogical data.