A Short History of Laos by Grant Evans is the best single-volume introduction to Lao history, covering the kingdom of Lan Xang through French colonialism to the communist revolution and beyond. Essential background reading.
The Ravens by Christopher Robbins tells the story of the American pilots who fought the secret war in Laos during the Vietnam era. A gripping account of one of the most heavily bombed countries in history.
Tragic Mountains: The Hmong, the Americans, and the Secret Wars for Laos by Jane Hamilton-Merritt is a deeply researched account of the Hmong people's involvement in the CIA's covert war. Moving and important.
Another Quiet American by Brett Dakin is a wry, perceptive memoir of two years spent working for the Lao national tourism authority. It captures the absurdities and charms of modern Laos better than any guidebook.
The Coroner's Lunch by Colin Cotterill is the first in a series of crime novels set in 1970s Laos, featuring an elderly Lao coroner. Light, witty, and full of local color. Great holiday reading.
Traditional Recipes of Laos by Phia Sing is a classic cookbook based on recipes from the former royal chef of Luang Prabang. If you fall in love with Lao food -- and you will -- this is the book to take home.
Ant Egg Soup by Natacha Du Pont De Bie is a food-focused travelogue through Laos. Engaging and full of recipes.
For current practical information, the Lonely Planet guide to Laos is regularly updated and useful for trip planning.