Isaac Asimov, The Collapsing Universe . 1977. Reprint, New York: Walker, 1989. Published before some of the major discoveries confirming many aspects of black holes, this volume is now somewhat dated. However, thanks to Asimov's remarkable skills in research and explaining difficult scientific concepts in simple ways, this remains one of the best general overviews of black holes, white dwarfs, and neutron stars. Highly recommended, especially for novices in the subject.
Mitchell Begelman and Martin Rees, Gravity's Fatal Attraction: Black Holes in the Universe . New York: W.H. Freeman, 1995. An excellent, highly informative discussion of black holes, including related phenomena such as stellar evolution and collapses, supernovas, white dwarfs, neutron stars, and quasars.
John Gribbin, In Search of the Edge of Time: Black Holes, White Holes, and Wormholes . New York: Penguin, 1999. A well-written, well-informed investigation of some of the more bizarre astronomical phenomena, along with the story of how scientists discovered them. Highly recommended. (This book was first released in the United States as Unveiling the Edge of Time .)
Clifford A. Pickover, Black Holes: A Traveler's Guide . New York: John Wiley, 1998. Very well written, this book makes the more difficult concepts about black holes and curved space very understandable and accessible. A clever and helpful added feature is a short dialogue between the author and an alien at the end of each chapter, foreshadowing the information that will come in the next chapter.
Edwin F. Taylor and John A. Wheeler, Black Holes: Introduction to General Relativity . San Francisco: Benjamin Cummings, 2000. This is an excellent study of the subject, but since it is on the scholarly side, it requires that the reader possess a fairly high proficiency in math.
John Taylor, Black Holes: The End of the Universe? London: Souvenir, 1998. A thought-provoking journey into aspects of black holes and what Taylor calls the "black hole universe" that most books on the subject do not attempt to address, including the ultimate fate of humanity—to be absorbed into and destroyed by a black hole, and the possibility that souls, if they exist, might be able to survive the big crunch. Intriguing.
Kip S. Thorne, Black Holes and Time Warps: Einstein's Outrageous Legacy . New York: W.W. Norton, 1994. Arguably the best book written so far about black holes and related phenomena. Combines history, science, and first-rate scholarship in an almost definitive statement about the effects of extreme gravity on the workings of space and time. Highly recommended.
Clifford Will, Was Einstein Right? New York: Basic Books, 1993. This award-winning book is a wonderful, easy-to-read exploration of Einstein's theory of relativity, which takes into account the concept of black holes. Highly recommended for those interested in curved space and black holes, or for anyone who enjoys reading about science.