In reply to dan tipper: "OISANS NOVEAU OISANS SAUVAGE Livre Est2" by Jean Michel Cambon is good for the higher stuff, I assume there is also a "Livre West" and "Grimper dans le Haut-val Durance" is good for the valley climbs, especially Ailfroide.
Depends where exactly you are going in the Ecrins and what sort of stuff you're looking to do...
The Oisans Est book covers only the Eastern areas I think. And it's all in French.
For the bolted stuff around Aielfroide there's a guidebook available in the village.
Same for the stuff around La Berade
For bigger routes in the mountains try the Oisans (2 volumes - E&W) books if you can read French.
Also, there is a guide to some of the sport climbing called "Grimper dans le Haut Val de Durance" or something along those lines. Covers some of the stuff in Ailefroide, plus Mont Dauphin and Ponteil etc.
You might need a few different guides to cover all eventualities. They are all available locally in Argentiere La Besse, Ailefroide etc.
Hi Dan i live just down the road from the Ailefroide, if you let me know what type of climbing you are after, e.g. single sports, multi pitch, alpine then i can let you know the best guides, there are some good local ones aimed at operating at a grade range to?