I cannot pick one book you need to read to understand the wealth of Black Books and their importance in communicating critical information that we all need to make this world a better place. 

Here is my short readers advisory:

I currently work in Multnomah County's Office of Diversity and Equity and our current book club book is 

Alexander, Michelle. The New Jim Crow: Mass Incarceration in the Age of Colorblindness. New York: New Press, 2010. Print.   The issues in this book are relevant to everyone! We all need to work on these issues regardless of race. This could be classified as a black book, but we all need to read it and take action on it. 

I am a librarian so I cannot just recommend one book. If you are new to reading about Rasicm I recommend

Wise, Tim J. White Like Me. Brooklyn, NY: Soft Skull Press, 2005. I like how Tim inspires us all to work on issues of rasicm and not hide from it, but instead "get pissed" and do something about it. 

If seeking black poetry, I recommend Alice Walker's "Her Blue Body, Everything We Know". Please read "Be Nobody's Darlin". I don't know one person who couldn't benefit from this poem. 

http://web.multco.us/diversity-equity/ode-book-club