Bridget Jones and the Constant Gardener are excellent and fairly easy reads. May I also recommend DaVinci Code and Angels and Demons by Dan Brown. They might be a little difficult, but they are really interesting. And to add to the classics list: Black Beauty and anything by John Steinbeck (since you want an American author, he is awesome, easy to read, I really recommend Travels with Charley, Of Mice and Men and the Grapes of Wrath are also really really good.)