Praised by critics and industry people alike (except, maybe, some of those talked about in the book itself), Sean Howe's Marvel Comics: The Untold Story is possibly the best account available out there the famous publishing house's history.
The books puts together in fine prose and chronological order a lot of facts, stories and anecdotes, (some well known in the community, some less) providing context and making it a very fun read.
You can read excerpts fom it on Google Books (also here) on Amazon and on author Sean Howe's own site.
Excelsior!