QUOTE (HDonaldCapps @ Jul 8 2009, 14:13)

Wasn't there a book that covered the sports/prototypes full of technical info that came out in the Eighties at some point? I cannot think of its name for the life of me. Plus, there were the Michael Cotton books on Group C, the Martin book(s) on IMSA GTP, and several (dozen) on the various Italian marques plus the same on the Aston & Jag & Cooper & Lotus as well as Lola and McLaren sports racers.
A Reader's Digest edition of all this is hard to put your finger on....
Siper Sports - The 220 mph Le Mans cars published by Haynes in 1988 covers the Le Mans type cars from 1964 to 1988, quite a lot of technical information in that.
I like this one because it concentrates on the cars rather than the races.
Osprey Motor Sport Endurance racing 1982 - 1991 by Ian Briggs in 1992 covers those cars and races.
Some of the information from that is used in Briggs's two volume Golden Era that covers Group C & Imsa from 1981 to 1993
One of the most interesting books on earlier sports cars is Specialist british Sport/Racing cars of the Fifties & sixties, but as the title says that only covers the British cars.
Janos Wompffen's other books are also intersting Open Roads & Front engines etc.
As you say, unlike for F1 cars, it is hard to find a Readers Digest sort of book - Time & Two Seats is probably the best and it can still be found for a reasonable price (e.g. try the publisher).