This book was written, printed and distributed privatly and is sold-out.
From what I heard I do not believe it's going to be updated and reprinted.
[update] just read he is distributing and sending you a digital copy, perfect [\update]
It is a nice book and, if your french is up to it, nicely written, it was the one of the first guidebooks giving more info about the country and discribing some of the rarely used and remote tracks. Amazing especially when you realise it was mostly done solo with a heavily adepted citroen 2cv (4x2).
The track info is sometimes a bit puzzling but, when you are used to it, accurated.
Although the geographie isn't changing the landscape is. So some of the pistes discribed are getting a bit outdated and nowadays most of the routes discribed you can find more-or-less updated on the internet, sometimes even digital and transferable for the navigation-device of your choice.
If you cannot find it second-hand, there are a few options:
if you are looking for country info:
The large english/french/german guidebooks like LonelyPlanet, RoughGuide, Routard, etc all have a small section about the country. The LonelyPlanet is supposed to be coming with a major update of their mauritania-chapter this year.
There are some small dedicated guidebooks, in french and german I know of (for instance, by HUBBmember
Edith Kohlbach) and the french PetitFuté has a nice one.
If you are looking for desert-info and pistes:
Offcourse you cannot skip SaharaOverland by HUBBmoderator
Chris Scott, although it's about more countries and everything that is involved with traveling in the Sahara, it is continously updated through his website and is heavily supported by lots of members on this forum.
There exists a french series of small guidebooks, every title discribes an area of the country (something like The Adrar, Routes de Caravanes, etc.) but I don't know who makes or distribute them, you can buy them at the campsite in Atar. Nice books, beautifull pictures but not very practical, the maps are very rough and the tracks are also getting a bit outdated. Very nice for planning short trips and as a souvenir back home.
Last year a new guidebook came on the market, written by
Jacques Gandini the same author who wrote a few guidebooks about Morocco (about tracks/routes and campings).
It is the best of both worlds, a lot of country-info, practical but also a lot of history (old and recent) and a lot of pistes and routes. Some easy (a few hours detour to a nice quelta, swimmingspot, doable with a 4x2) some serious (expedition-style).
The info is sometimes overwhelming (and in french) and the routes are not discribed in the most easy usable format, the waypoints are distributed throug-out the text instead of presented in a list, and sometimes it seems they are only 200m apart (which gives too many waypoints for my oldschool GPS). But it is very accurate.
I think it is probably the best you can get at the moment and the whole book speaks of a big respect for the country, desert and people.
I'm sure there must be more to find.