For the dust, I would get a California Car Duster. These do a great job of removing dust (provided it hasn't been rained on already). They work like a feather duster, but they have a mop-like yarn head that you lightly brush over the car. One the days that I use mine, it takes all of about 1 minute to swipe it across the whole car.

Desert climates would be perfect for this product - sadly, in my area, I don't get to use it that much, since once the dust gets rained on, it is stuck until the next washing.