Spoken Here: Travels among threatened languages by Mark Abley (2004)
Mark Abley is a travel writer who has here written about endangered languages in a way which is accessible and wonderfully readable. He has done his homework on language extinction, then travelled to places to talk with, walk with, experience the lives and language of the few speakers left of a dozen languages in extreme danger.
First among them is the language of the Mati Ke people near Wadeye, of whom there are two left. Abley details the history of its speakers, who after generations of living on reserves in the area only speak the Murrinh-Patha language, and tells of his visit there. It is not easy reading.
What I especially like about this book is its informative combination of comparative anthropology and good linguistics, and great story-telling. Abley has a knack for making the science of linguistics human. Also, it has a happy ending, with three chapters on successful language revival.