Allow me to second Goingboeing's rec on "Destination Disaster"
I just found a used copy on eBay a few weeks ago to replace the one that I lent out (never got it back) and I found it far better than another book of the era "The Last 9 Minutes." In particular, the chapter dealing with the memo by Dan Applegate (engineer at Convair, the fuselage subcontractor) is must reading, espectially since the failure that brought down THYhad occurred twice earlier.
If you can't find DD at your local library, check out the auctions at eBay, yahoo, or elsewhere to see if you can find a copy. It'll be well worth the cost, and the context and explanations in the book with respect to other related matters is excellent.
ALL views, opinions expressed are mine ONLY and are NOT representative of those shared by Southwest Airlines Co.