I have both books you mentioned.
The first was compiled by R.M. Clarke, Shelby Cobra: Gold Portfolio 1962-1969, and published by Brooklands Books Ltd./Motorbooks International in 1990 (ISBN 1855200236). This is one of many good compilations from them of Cobra articles.
The second was written by Iain Ayre, The Essential Buyer's Guide: Cobra Replicas 1980 to 2011, and published by Veloce Publishing in 2011 (ISBN 1845843959). I'm not impressed with this one at all.
My Cobra book and memorabilia collection is listed here, if you're ever looking for some ideas.