The Switch by Joseph Finder

If you're looking for a real page-turner during these waning days of summer, you can't go wrong with The Switch. It all starts simply enough. Coffee entrepreneur Michael Tanner is rushing for a flight and grabs the wrong laptop after going through the airport security line. He doesn't realize it till he gets back to Boston. When he turns it on to see if he can identify the owner of the laptop, he realizes he has a U.S. senator's computer and it contains top secret files about a nefarious program that the government is thinking of instituting. Oh oh. That's when Tanner's troubles begin. The senator's assistant is trying to get the computer back using increasingly devious means. The NSA is trying to get the computer. As are the Russians. Tanner soon realizes that his life--and the lives of his friends and family--are in real danger.

For someone who's not a techno geek, he's a quick learner about government surveillance and comes up with some pretty creative ways to stay below the radar. But he's just one guy, who's also dealing with business and personal issues while trying to stay alive, so there's a lot of suspense about just how long he can last against all his foes. I read the whole book in less than a weekend--and will have to search out more works from the same author. Quick read. Good story. Good main character.