Reference resources are a great place to begin your research. They can help you define terms as well as to find basic information about a topic, a chronicle of its history, theories, key people and sometimes a bibliography of additional sources.
There are many different types of reference sources, which include dictionaries, encyclopedias, thesauri, bibliographies, handbooks, style manuals to name a few.
Selected Resources include:
Album of American History
E178 .A2 A (5 volumes; Stauffer – Books)
Atlas of the Civil War
G1201 .S5A85 1994 (Maps)
A Companion to American Cultural History
Also E169.1 .C684 2008
Encyclopedia of American History
REF E174 .E53 2003
Historical Times Illustrated Encyclopedia of the Civil War
REF E468 .H57 1986
Oxford Companion to United States History