Using a typewriter, "
is the correct form to denote the quotation mark in German.
For text written by hand and letterpress printing in Germany we use „“
Currently these characters are displayed here by the Verdana font „“.
Hopefully when this site leaves beta, it will get a default font, which renders these characters in a correct way. I have seen Home improvementHome improvement leaving beta and they got a different font.
If we type „“ now, it will automatically be rendered in the correct way after we leave beta.
I found a further tool to type these characters: Type German characters.
There is a similar tool to type IPA phonetic symbols.
Both tools are web pages, i.e. no installation required.