This is the Jon Evans title ATDrake mentioned that wasn't available to Canadians but it is free to Ukers. Published by HarperCollins and St Martins back in 2006 or 7.
by Jon Evans
In a world where security cameras prove what you have done and databases define who you are, the few who know how to manipulate the technology can play God. They can change the future; they can alter the past. They can make big money, they can save the world, and they can get away with murder over and over again.
Danielle Leaf grew up believing she was safe. Now she knows she was wrong.