Here are some suggestions. However The Uchronia Website has 1823 entries
www.uchronia.net/. Please note that the divergence point does not always equate with the period of the story
John Christopher Fireball Trilogy divergence point Roman Times
Kingsley Amis The Alternation divergence point the reformation
Keith Roberts Pavane divergence point the Armada
Divergence Point The American war on independence
Harry Harrison A transatlantic tunnel hurrah hurrah
Harry Turtledove The Two Georges
Robert Sobel Fore want of a nail
Divergence Point the War of 1812
Eric Flint 1812 Rivers of war 1832 the Arkansas war
Divergence Point the American Civil War
Robert Conroy 1862
Newt Gingrich The Gettysburg Trilogy
Harry Harrison A rebel in time (time travel variation)
Harry Harrison Stars and Stripes Trilogy (not the authors best work)
Ward Moore Bring the Jubilee (+a time travel twist)
Divergence Point World War 1
Saki When William came
Divergence Point World War 2
Stephen Baxter Weaver
Robert Bowen No retreat
Newt Gingrich 1945, Pearl Harbour and Day of Infamy
Owen Sheers Resistance
James P Hogan the Proteus Operation
Christopher Priest The Seperation
Divergence Point the Cold War or Space Race
Eugene Dubois The Resurrection
Stephen Baxter The voyage
Parallel Worlds
Taylor Anderson The destroyermen trilogy
Keith Laumer The Other Sky, World of the Imperium, Assignment in nowhere
Michael Moorcock Warlord of the air trilogy (tails of by 3rd book)
Alternate History as fact
Robert Cowley What if, More What if and Whait if America
Nial Fergusson Virtual History (Academics tending to argue how history could have run differently rather than the effects)
Duncan Brack and Ian Dale Prime Minister Portillo and other things that never happened and President Gore and other things that never happened (only read it if you are interested in politics)
Dystopias
Eric Blair 1984
Ray Bradbury Fahrenheit 451
Warwick Deeping Compuer one
Aldous Huxley Brave New World
David Karp One