German Federal Film Board
The role of the FFA is to promote and improve the structure of the German film industry. It is also responsible for the German Federal Film Fund.
ffa.de

German Film Service + Marketing GmbH
The national information and advisory center for the promotion of German films worldwide.
german-films.de/en

FOCUS Germany
Companies looking to partner with a German production company can seek the help of FOCUS Germany, an organization created in 1990 to aid filmmakers looking for info on funding and production opportunities.
focusgermany.de

Regional (lander) funds
Each region in Germany has its own fund to encourage filming in different areas of the country. Here is a sample:

Berlin-Brandenburg Film Commission:
bbfc.de
Bayern Film Commission:
film-commission-bayern.de
Baden-Württemberg:
mfg.de/film/
Hamburg Film Fund:
ffhh.de
Nordrhein-Westfalen Film Fund:
filmstiftung.de
Mitteldeutsche Medienförderung:
Mdm-online.de
Lower Saxony and Bremen's nordmedia:
nordmedia.de