A. I would focus on something written for the Las Vegas climate or secondly Tucson, Arizona and lastly the desert Southwest. Books I suggest are available on Amazon and Abe’s Books as well as other places if you search using the author names.
Linn Mills from Las Vegas and Dick Post from Reno teamed up and wrote a book called the Nevada Gardeners Guide that has information split between both northern Nevada and southern Nevada. Its focus was to understand both Mojave Desert (Las Vegas) and Great Basin (Reno) conditions, soils and how to manage a landscape growing in them.
Tucson has a similar climate to Las Vegas; a bit warmer and humid in the winter and wetter during the summer months. From here is Plants for Dry Climates by Mary Rose Duffield and Warren Jones. It includes desert landscape design ideas as well. The newest edition includes and expanded section plant selection and care.
Adjust books not written for the Las Vegas by recognizing that our winter low temperatures can get into the low twenties and even the upper teens on occasion. Trees you select for the “backbone” of your desert landscape should withstand these temperatures or you are asking for trouble. Play around with lesser important landscape plants that don’t tolerate these temperatures but don’t expect them to survive forever.
A solid reference book is the Sunset Western Garden Book. It is not specific for the Las Vegas area but does a good job discussing desert soils, desert environments as well as an exhaustive list of plants suitable for advanced gardeners.
I use Chris Martin’s Virtual Library of Phoenix Landscape Plants, free online and housed at Arizona State University, quite a bit. Just realize plants discussed are used in the Phoenix climate and soils. Adjust your selection for our colder winter temperatures and not as much heat in the summer.
Several knowledgeable local experts like the Southern Nevada Water Authority (SNWA) searchable database of landscape plants for Las Vegas, called “Find Plants”. It is a good online reference when first looking for possible plants to use.