This article is from the U.S. Civil War FAQ, by Justin M. Sanders firstname.lastname@example.org with numerous contributions by others.
The books on this section of the list are here as valuable references, and
are not something that you would actually sit down and read. However, if
you want to look something up first-hand, these are the books in which to
Mark Boatner, The Civil War Dictionary. (reprint, 1988).
A dictionary of Civil War names, places, battles, and terms, with one
paragraph descriptions of each. Designed as a quick and easy reference to
let you get a quick grasp of a subject starting from only a name or place.
Dornbusch, Military Bibliography of the Civil War. 4 vols, 1987.
A listing of books published on Union and Confederate regiments, and
personal narratives. 1987 is the latest update. An ideal way to track down
the wartime experiences of a relative whose unit is known.
Frederic Dyer, A Compendium of the War of the Rebellion. 3 volumes.
A summary of the portion of the Official Records which deals with the
Union armies: contains much of the interesting information and numerical
data without the dross and kipple of the complete Records. Useful if you
want to find something that is in OR but don't have the time to hunt
William Fox, Regimental Losses in the American Civil War. 1985.
Regiment by regiment, lists all the losses suffered in the various
battles of the war. Also contains synopsis histories of each corps in the
Union Army, and a fair amount of other very interesting information.