Well, it´s time to share.
A long time ago, in the internet infancy, I contacted Jane´s Information Group to buy Fighting Ships.
Of course, with a US$ 700 price, I backed off.
But the a nice man pointed me to
http://www.scholarsbookshelf.com/ , the place where older editions (2004/5, 2003/4) ended if not saled.
Along the years, I bought Fighting Ships, All The World´s Aircraft, Land Based Air Defense...at 1/10 of the real cost.
For example, Jane´s Underwater Warfare Systems 2003/4, originally $ 557, costs now $ 25.
Of course, I´m not affiliated with the book store. Just want to share one of my best kept secrets...