Locating and identifying major DH research projects in German-speaking countries is a large task without knowing the vocabulary and agencies involved. Usually, the easiest way to learn about current DH research projects in Germany is to first identify the major research centers at universities, then look at their projects. Alternatively, national assocations for DH in Germany also offer publication information and current project information.
Below are some selected DH projects, but there are many more out there!
This brochure from the Cologne Center for eHumanities at the University of Cologne outlines 27 academic programs for studying digital humanities in Germany. The introductory sections provide a definition of digital humanities, how academics study digital humanities, career prospects in the field, etc. Overall, the brochure provides an excellent overview of the breadth of digital humanities applications. While specific projects are not listed, the programs at each university are explained in detail, so this information should point you toward German DH projects.
German linguist Noah Bubenhofer has created an excellent German language introduction to corpus linguistics. His web content falls within the concept of digital humanities because in his instructional materials, he studies whether the internet itself could be a linguistic corpus as well as database programs, statistics, etc. This website will only be useful to the most advanced readers in German, as the website seems jargon-heavy. 
TextGrid is a German research project, funded by the federal government, that seeks to create a virtual research environment for digital humanities work.
