Insects of the Southwest, Floyd Werner, Ph.D. and Carl Olson, M.S., Fisher Books, 1994. Eight chapters of creepy insects. Great drawings and no nonsense text tell you everything you want to know (or not want to know) about Southwest insects.
Gardening Success With Difficult Soils, Scott Ogden, Taylor Publishing Company, 1992. Everything you need to know if you have limestone, alkaline clay, or caliche soils. (That means everybody should already have this book!) Highlight is the list of heat/drought tolerant plants that love these soils and tough conditions.
Plants for Natural Gardens and Natural by Design, Judith Phillips, Museum of New Mexico Press, 1995. You can purchase these two books separately or as a beautifully boxed companion set. Plants for Natural Gardens showcases over 180 plants native to the high desert. Highlight is the propagation technique for each plant. Natural by Design teaches the principles of design, planting, and maintenance. Gorgeous pictures.
All of these books are available in the Cochise County Library District including the local city libraries of most towns and cities of the county.