The following books are of use to members and prospective members of Black Greek Letter Organizations. I have listed them in order of relevance to laymen. In other words, the first one is very general information and the last one is so advanced it probably won't be relevant to anyone but higher ed professionals.
Nonfiction, General BGLO Interest
The Divine Nine: The History of African American Fraternities and Sororities
Black Greek 101: The Culture, Customs, and Challenges of Black Fraternities and Sororities
Black Haze: Violence, Sacrifice, and Manhood in Black Greek-Letter Fraternities
African American Fraternities and Sororities: The Legacy and the Vision
Black Greek Letter Organizations in the 21st Century: Our Fight Has Just Begun
Black Greek-Letter Organizations 2.0: New Directions in the Study of African American Fraternities and Sororities
Organization Specific Books
Alpha Phi Alpha: A Legacy of Greatness, the Demands of Transcendence
Disciplining Women: Alpha Kappa Alpha, Black Counterpublics, and the Cultural Politics of Black Sororities
In Search of Sisterhood: Delta Sigma Theta and the Challenge of the Black Sorority Movement
IOTA PHI THETA - The Founding and Ascendancy
Novels
Sorority Sisters
Lazarus <------- Full disclosure: Senusret I wrote this.
If it's not on this list, I probably don't recommend it.
A note on official history books: As many aspirants have surely noticed, you can use
www.abebooks.com or ebay to locate official history history books of many, if not every NPHC organization. However, they are very very expensive. It is highly unlikely that you will find anything in the official history books which will give you an edge on any other aspirant. It's not a history competition -- the best (and dare I say only) way to become a member is to meet the members, interact with the members, and befriend the members. We don't vote yes based on how much information about us that you know. The official websites are always the most current, official sources of information. Even all of the books listed above aren't necessarily official, even though they cite official sources. So save your money rather than spending hundreds on rare books. If you cross, you'll get more information than you ever could ask for.