This thread on Hacker News has a lot of interesting sounding suggestions for books on computer history.
https://news.ycombinator.com/item?id=22692281
Some books that got multiple enthusiastic mentions:
Dealers of Lightning: Xerox PARC and the Dawn of the Computer Age
The Dream Machine: J.C.R. Licklider and the Revolution That Made Computing Personal
Where Wizards Stay Up Late: The Origins of the Internet
Turing’s Cathedral: The Origins of the Digital Universe
The Innovators: How a Group of Hackers, Geniuses and Geeks Created the Digital Revolution
The Soul of a New Machine
Hackers: Heroes of the Computer Revolution
The Code: Silicon Valley and the Remaking of America
The Information: a History, a Theory, a Flood