Paul Youngman, an associate professor of German Studies at Washington and Lee University, chairs the Digital Humanities Action Team (DHAT) at Washington and Lee University. Some of his upper-level German classes have used written analysis and mapping functionalities for digital humanities. One of those example projects is Kulturkarte (linked above).
Gerhard Lauer is the Chair for German Studies at the University of Goettingen and Head of the Goettingen Center for Digital Humanities. His professional website includes great downloadable scholarly content, including publications and columns. Both English and German-language materials are available.
AT MIT, Kurt Fendt is the Executive Director of HyperStudio and also teaches upper level German courses. One of his projects offers German language learning through digital humanities, called Berliner Sehen (linked above).
MSU’s German department has a digital humanities component in their PhD program. If you are interested in searching for Germanists in the US who are conducting digital humanities research, this program may be a useful start.