All you need to do, in order to get yourself prepared for the 1. Stufe, is to get a book with FAA questions - thats what they use (and they are in english of course). I reckon the level is CPL - not ATPL (chk out the book by Kershner if You dont already have it). No sweat. But when it comes to 2.Stufe. Sweat! There is a german book called "piloten-test" by Hesse Schrader. Its useful. Good luck! P