I recently came across Steve Blank's Secret History of Silicon Valley series of blog posts. The essays do a wonderful job of dispelling the myth of Silicon Valley as "a bunch of orchards and then Hewlett & Packard came along." As with the East coast universities and research institutes that were instrumental in creating the computer revolution, it was the military that turned out to have provided the resources for the start of Silicon Valley as we know it today (although in the form of the Air Force and not DARPA).
The East coast/DARPA contribution to the computing revolution is described in detail in M. Mitchell Waldrop's The Dream Machine: J.C.R. Licklider and the Revolution That Made Computing Personal. Blank's essays and The Dream Machine do a very thorough job of detailing the rise of today's computer industry; I consider the latter essential reading and am now happy to add the former to the same category.
Howard Rheingold's Tools for Thought is an interesting, light overview of the broader history of modern computing machines from Charles Babbage to Ted Nelson (the first edition was published in 1985, back when hypertext was still hypertext and there was no web).