I have that book at home, have read it. Very interesting! I suggest, to further your reading, a rather dry but nevertheless interesting book about that region: Yuman Tribes of the Gila River, by Leslie Spier:
http://www.amazon.com/s/ref=nb_sb_noss? ... ikearizona
Also: The Gila River of the Southwest, by Edwin Corle (which you probably have seen before, but I'll include for the benefit of the group)
http://www.amazon.com/Gila-River-Southw ... ikearizona
If you want to kayak the lower Gila, it is possible during certain irrigation seasons, when a lot of water is dumped in, you can start in the Mohawk Valley or Dome Valley. At least, that is what I'm told by friends. Or after a flood season, when it has slowed down a little. I have kayaked the last half mile of it, to the confluence, and thence down the Colorado, and passing under the bridges, and past the historic part of Yuma, and taking out at West Wetlands Park. Sounds long, but actually takes only a couple of hours. This latter trip can be done almost any time. The hard part is locating the put-in! I can't describe that, just know how to find it out on the levee roads. You could put in on the Gila at the last bridge, perhaps. That would be on Laguna Dam Road. Sometimes it is pretty low, though. It is DIRTY, too, it is all irrigation runoff. But there are a LOT of birds and animals along there. My friend saw the elusive Arizona Clapper Rail. Hope this is not "TMI." ;)