The Research Explorer, a database of the DAAD, lists all research institutions, both at universities and non-university on the German Science Landscape.
The Internet portal Research in Germany is providing information for postdocs about research institutions, funding possibilities, job ads, research groups, junior chairs etc.
Federal Funding Advice Bureau "Research and Innovation"
The Funding Advice Bureau of the German Federal Government offers first-hand information on research and innovation funding. Potential applicants can find out about the German research landscape, funding programmes and their contact persons as well as current funding priorities.
EURAXESS is a pan-European initiative providing access to a complete range of information and support services to researchers wishing to pursue their research careers in Europe or stay connected to it.
Academics.com offers a wide variety of relevant articles to advance your career. Here you find information on funding, salaries and alternative career paths outside of academia in Germany, Austria and Switzerland.