Do you have any friends that speak German?
(It is hard to be in Germany without speaking German, I think. Especially with those... Oops. No Bavarian bashing...

)
How long will you still be there? (If it is not more than a month, you should be able to survive the time. Oh, and some of the more frequently ordered RPG books might even be deliverend in 24 hours or 2-3 weeks. But than, there is still the language problem - amazon.de is german)
Hmm. A further alternative might be that you just try to go to an ordinary book store, and ask if they can order it. I can easily imagine that some people there can speak English (maybe even Spanish

), so you might give it a try.
In Germany, the book delivery system is quite good, as far as I know (and experienced).
German books might be a bit expensive than in other countries, because of the "Buchpreisbindung", but at least the quality is good

.
Mustrum Ridcully
PS:
The CSU is a political party that only exists in Bavaria and reign their for several years ... (On "Bundesebene", they are allied with the CDU)