Nonfiction can range from biographies to history. The topics for these type books must be researched. Some history books may take a scholar years to complete. It may be tedious and boring at times but there is no other way to get the job done. There are many, many resources to do research on line. If you are attending a university you have some of the best libraries in the world. We take our libraries for granted in the US. Many countries do not have public libraries.
You can also find information about Geography and History, Religion, Occultism, Philosophy, Parapsychology, Philosophy, Social Sciences, Language, Natural Science and Mathematics, Technology, The Arts, and Literature and Rhetoric.
Cornell Universities Making of America site has a vast Bibliography of books and articles. A person could spend a lot of time doing research about history on this site. There are also links to war history including the Civil War. It is called The War of the Rebellion on Cornell's site. It is also know as the Great War in some areas of the US. In the south we usually refer to it as the Civil War. The complete scanned texts are made available. They are called Multi volume Monographs. http://cdl.library.cornell.edu/moa/
Please visit the Archiving of America web site at: http://www.earlyamerica.com/. It is a well done site with excellent jpegs of original documents about the founding of our country starting with the "Declaration of Independence" and ending with "Notable Women of Early America". If you want copies of your own you must order them. {I am in no way affiliated with this web site. It is suggested as a tool for research into American History.}
Complete on line texts of books of major importance in the areas of economics, urban school reform, urban affairs, international affairs, international economics, defense policy, general economics, education, and government and politics.
RESEARCH AT BROOKINGS INSTITUTE
This web site has a range of scientific papers on subjects ranging from medical, climate changes, nano and quantum computing . The submit tees of articles are scholars in their chosen fields. http://www.brookings.edu/index/research.htm
Proceedings of the National Academy of Sciences of the United States of America http://www.pnas.org/
Archives of the on line magazine since January 01, 1990