Ronin Ro, Raising Hell: The Reign, Ruin, and Redemption of Run-DMC and Jam Master Jay (2005)
Ro gives an excellent, personal, and detailed story of the band's history that manages to put you right there next to the musicians as they revolutionize hip-hop.
Jeff Chang, Can't Stop Won't Stop: A History of the Hip-Hop Generation (2006)
If you ever find yourself asking why something happened in hip-hop, read Jeff Chang's book, which explores the geographical, socioeconomic, political, and historical context of how hip-hop came to be and what it has become.
Marcus Reeves, Somebody Scream!: Rap Music's Rise to Prominence in the Aftershock of Black Power (2008)
Reeves tells the story of hip-hop through ten artists, from Run-DMC to Eminem, and explores the politics of the black generation that grew up after the Civil Rights Movement and Black Power.