Here are a few that I could find....
Amazon
http://www.amazon.com
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Indy Cars of the 50's by Karl Lugvigsen
Barnes and Noble
http://www.bn.com
...............
Technology of the Champ Car by Nigel McKnight
Vintage and Historic Indianapolis Cars by Dan Owen
Indianapolis Race Cars 1961-1969 by dave Friedman
Anatomy and Development of the Indy Car
Indy Car Champion: A Season with Target-Chip Ganassi Racing by Ned Wicker and Cheryl Anderson
Nigel Mansell's Indy Car by Nigel Mansell and Jeremy Shaw
Indy Race Cars by Autosport International
Indy Car 93-94 by Kris Perkins and Shaun Barrington
Try these book out. Barnes and Noble seems to have a better selection that Amazon on this subject matter.