I just got back from leading a trip through the Grand Canyon.  I am posting the entries from my daily log on my blog.  Though words could never adequately reproduce the experience, if you have never been, this might give you a better understanding of what it is like.  It includes lessons I learned along the way too, so if you're planning to lead a trip, you might find something useful.
The story begins here:  http://thenotesguyinseattle.com/2011/11/27/grandadventure/

Cheers,
-David