Remember the Nikon D400 book story from Germany by the author Michael Gradias? It was covered multiples times here on NikonRumors (post 1, post 2 and post 3). Well, this rumor was almost true (except the actual book name). The book is now available for pre-order on Amazon Germany under the name Nikon D300s with the same ISBN# 9783827244826 and from the same author:
If you need a Nikon D300s book in English, those are your options: