Hi fct ..
This will most likely be a general set up guideline type of book. Frankly, I would find some of your local giant scale pilots and talk with them.
Of course, everybody has a slightly different opinion on aircraft setup.. but the solid basics can be aquired from freinds, the internet, and books last of all.
You might check into the IMAA.. I am pretty sure they have a chapter in Germany.
Good luck !
Of course.. you can always ask here !