cob in Arizona

I am quite new to the whole idea of alternative building. I am going to move to Sedona AZ this fall and would love to buy a small piece of land one day to build a cob house. WHat kind of things do I need to keep in mind? How would cob do at keeping the indoor temps down? THe house I designed is on one level because I thought a loft would be too warm. Is this accurate?

There are three books on cob building: The Hand-Sculpted House by Ianto Evans, The Cob Builders Handbook by Becky Bee, and Building With Cob by Adam Weismann. I haven't looked at the third one, but the first two are both excellent, and will answer all your questions. HSH goes much deeper into things like choosing a site and why cob is good, but I find its actual instructions to be too restrictive, while CBH has more of a "whatever works" attitude.

Cob has huge thermal mass but is not a great insulator. If you do it right, it will store the night's cold temperatures and keep the inside cool during the day.

I think cob would do fine in Sedona's climate...

It's properties are similar to adobe in terms of the functioning of the thermal mass.  Desert climates are great for this sort of building, as it takes advantage of the difference in temps between day and night.

Nothing wrong with a loft...you can use the difference in temp between upstairs and downstairs to your advantage.  Unless you are nocturnal, you won't be in the loft during the heat of the day, only at night when the accumulated warm air might be welcome, depending on season.  Of course, a well placed vent would be key.

I would also look into incorporating living roof, earth tubes, evaporative cooler (swamp cooler), and strategic plantings for other climate control features. 

Dunno about the legalities of cob in AZ.