Thanks to Ivan Horvat we now have the dopdf.com website available in German too: dopdf.com/de/.
If you want to help us translate the website (or the interface) in a language that's not yet translated in, you can start by visiting this page: Languages. You'll see there in which languages doPDF is not translated, and if you want to help you'll simply have to email us and we'll reply with details. Practically the website has about around 1200 words that need to be translated.