The Pat Series is a nice training-
There are several books available. At first the books with the official tests themselves, and 1 or 2 additional training-books- these books i can really recommend. (i m not sure if any additional books are also available in english-but i ll try to get the info). The DVD s are very interesting imo. And the first DVd is one of the best i ve ever seen. The first 20-30 minutes of DVD 1 are about fundamental technics and explained by Andreas Huber and Ralph Eckert, two absolutly pro-instructors (Huber also german team instructor, crazy guy !)
The additional training books showing step by step to solve the problems on the 3 official tests. If you like to work solo-get em all. Imo all the money worth.