Surprisingly seem like there isn't even one book in English has good working code of a complete backtest/trading system simple.
Sure there are, "The Compleat Day Trader" by Jake Bernstein for example has the TradeStation code plus the backtest results of some of the systems. But you are right, almost 99% of all trading books/seminars never show you any backtest, you just have to trust them and hope their systems work
I don't consider any "easy language" book shows how to build trading system, I only count any using real programming language. By the way, Jake Bernstein is only infamous for: In 1999, Bernstein was fined by the National Futures Association $200,000 and permanently barred from NFA membership for using misleading and deceptive Promotional Material. http://en.wikipedia.org/wiki/Jake_Bernstein