Unfortunately German comics and cartoons industry is dominated by foreign productions. Slim pickings here. Possible recommendations for adults:
Nick Knatterton comics (a bit dated)
Das kleine Arschloch (comic and Kleines Arschloch a 1997 animated feature film)
Der alte Sack
Adolf, die Nazisau
Brösel: Werner comics (and several cartoons)
Felidae (1994) a cartoon based on Akif Pirinçci's cult novel.