In reply to Steve434:
If you haven't already seen it, I'd recommend Des Clark's excellent "Mountaineering in the Moroccan Atlas" (Cicerone) and "Moroccan Atlas, the trekking guide" by Alan Palmer (Trailblazer).
People often arrive at the Toubkal huts at 3200 mts, having come from sea level, suffering from altitude sickness (we encountered a Brit there in a very bad way). Good hydration and a measured pace are strongly advisable.
This video is primarily about our ice climbing trip but there is a link in it that takes you to various posts you might find of interest. They cover the walk in from Imlil, via Sidi Chammharouch up to the Mouflons hut (we preferred it to the Nelter hut in the same vicinity), as well as an ascent of Toubkal (spectacular views of Sahara and Atlantic ocean).
http://www.kragrags.com
It was 27 C in Marrakech in January, I imagine it could be pretty uncomfortable in the summer.