http://www.summitpost.org/route/155414/cooper-spur.html
Summitpost.org has a wealth of information, history, and photos.
To answer psistrom earlier; I think it's just above the Chimneys area of the NF above Cooper Spur.
Check out http://www.summitpost.org/mountain/rock/150189/mount-hood.html#chapter_2
as well.