Geocaching is very a pivotal part of the plot for this book and sets up the adventure/mystery.
The scenery in the book is authentically the White Mountains area of Arizona. Between Pinetop/Lakeside and Eager/Springerville on the AZ 260. Near the Sunrise Ski Resort. You can go to Greer, AZ (take AZ 373 - The "road to nowhere" and find all of the places mentioned in the book. Although they are named slightly differently, there are plenty of familiar landmarks. There is a general store with cabins and a trail where elk and wildlife are running about. And many geocaches as well to find in all these areas.
It is a beautiful part of the country and is often overlooked by anyone but AZ residents because of the Grand Canyon being in the other quadrant of the state. That of course is very beautiful in its own way.
That being said, Greer has some good fly fishing, hunting in season, and other outdoor activities. There are plenty of cabins to stay at that are pretty reasonable.
This area is about 2 1/2 to 3 hours NE of Phoenix and is actually closer to the New Mexico border. If you ever get the chance you should go. The area was touched by a big fire in 2011 but most of the forest did survive intact. Most of us in PHX escape the heat there in summer and go skiing in the winter.