Sky and Telescope News
NASA: Messier Objects
Astronomy: A Beginner's Guide to the Universe. By Eric Chaisson and Steve McMillan. 5th edition. Pearson/Prentice Hall, 2007.
Skywatching, by David H. Levy and John O'Byrne
Deep Sky Objects: The Best and Brightest From Four Decades of Comet Chasing. By David H. Levy. Amherst, Prometheus Books, 2005.
NightWatch: An Equinox Guide to Viewing the Universe, by Terence Dickinson
Turn Left at Orion, by Guy Consolmagno
The Stars: A New Way to See Them, by Hans Augusto Rey
The Backyard Astronomer's Guide, by Terence Dickinson and Alan Dyer
Burnham's Celestial Handbook: An Observer's Guide to the Universe Beyond the Solar System, by Robert Burnham, Jr.
The Complete Manual Of Amateur Astronomy, by P. Clay Sherrod
Constellations are from PP3 Sourceforge freeware program