This guy named Tuan (sp?) has climbed there a lot and has got a wicked amount of info on his website. Compleate with route suggestions, were to stay, were NOT to stay, and such.
Follow the link sucka
http://www.ai.sri.com/~luong/mountain/chamonix/
BTW, I think I have some pics of Grand Jorasses floating around on my harddrive with route over lays, should you want to see them