It costs 0.012 eurocents per minute to call Germany from anywhere in the world with something like voipbuster.com.
I really don't get why one would want to be stubborn about not phoning a company one has trouble with. Clearly it's not being resolved via e-mail, heck even sending a paper letter costs a few quarters. Print your e-mails and stuff them in an envelope if you absolutely won't use the phone!