If the OP is still looking for the books, they are available in the US from Barnes and Noble
http://www.barnesandnoble.com/w/litt...=2940149851928
That goes to the first book in the series, but I was able to buy them all.
Shari
Edit: Oops--I just noticed that the OP is in Germany. Sorry...I don't think you can buy from Barnes and Noble if you're in Germany.