I know that "Paper Money of the United States: A Complete Illustrated Guide With Valuations" by Arthur & Ira Friedberg, was tops back in the 1990's not really sure what is the most current or best book today. I'd recommend that as a really great starter book for your library.
Amazon shows it's current edition is the 18th, updated to 2007. It was originally based on Richard's work covering 1912-1963.
It covers large size notes, fractional currency, small size notes, encased postage stamps from the first year of paper money (1861) to the present (2006) and it also contains sections on confederate states notes, colonial and continental currency, as well as error notes.
For National Bank notes there are many specalized books writen and usually quite expensive, same goes for the Confederate notes (Grover Criswell wrote some of the top references covering Confederate notes and the Civil War era currency).
"Standard Guide to Small-Size U.S. Paper Money 1928 to Date" by John Schwartz & Scott Lindquist, seems to be the go to book for any currency produced after 1928. I don't have this book, yet, and it seems like from the
Amazon reviews, there are some quite glaring errors through the 7th edition, so read the reviews on the books as always. The current book is up to the 10th edition.
Hope that helps a bit, I'm sure others more knowledgable in currency will chime in soon, and if they don't put a word in at the US paper money forum.
"Buy the Book Before You Buy the Coin" - Aaron R. Feldman - "And read it" - Me 2013!
ANA Life Member #3288 in good standing since 1981, ANS, Early American Coppers Member (EAC), Colonial Coin Collectors Club member (C4), Conder Token Collector Club member (CTCC), Civil War Token Society (CWTS) member, Liberty Seated Collectors Club (LSCC) & Numismatic Bibliomania Society member (NBS), USMex, Member in good standing, 2¢ variety collector.
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