There are diverse opportunities for research funding. Information about financial support programs of the EU, the Federation, and the German States can be found in the data base of grants of the Federal Ministry of Economics and Technology.
academics.de, a database of academic awards, lists all awards according to subject areas.
The foundation index offers an overview of foundations existing in Germany.
Announcements of support programs and awards can be found under the heading of calls for proposals, organized by academic field. You can subscribe to an academic field folder if you want to be informed about new announcements.
You can find the current calls for proposals of the Excellence Initiative here.