As far as I know there's no guidebook in English for this region apart from this one which lists a few easy trips in the area.
But since canyoning in southern France is very popular there are usually information boards at the top of each canyon with a complete Topo, marked emergency exits and all kinds of other informations. Go to descente-canyon.com look at the map and filter for the highest rated canyons to get an idea where to go.