Bill O'Reilly: US$28 million

He'll always be known primarily as a television talking head, but with the publication of "Killing Lincoln," book writing became more than just a sideline for the Fox News host. After the publication of follow-up "Killing Kennedy," he held the No. 1 and No. 2 slots on the New York Times hardcover non-fiction best-sellers list, and his next volume, "Killing Jesus," could be the biggest of the series.