If you liked "Letters from Yellowstone" you might enjoy these titles:

• The Queen's Fool, by Philippa Gregory
• Outlander, by Diana Gabaldon
• Guardian of the Horizon, by Elizabeth Peters
• Devil Wears Prada, by Lauren Weisberger
• March, by Geraldine Brooks
• Pictures from an Expedition, by Diane Smith
• A History of Environmental Politics Since 1945, by Samuel P. Hays
• American Environmentalism: Readings In Conservation History, by Roderick F Nash
• Crimes against Nature: Squatters, Poachers, Thieves, and the Hidden History of American Conservation, by Karl Jacoby
• The Beast in the Garden: A Modern Parable of Man and Nature, by David Baron