When Michael Jackson died this past summer, he had nearly a half a billion dollars in debts. Since then, it’s been a great year for his career: lawyers for his estate say they have lined up merchandising deals worth $100 million, and surging record sales and other income will produce another $100 million.

And this is not unusual. Decades after their demise, some departed stars continue to work on new projects and draw more income than they ever made while drawing breath. And there is a growing legion of agents and managers willing to represent them.

Dead celebrities can be just as lucrative as many live ones, and in some cases, a lot less trouble.

No other agent in the world represents more famous people than Mark Roesler: stroll down Hollywood Boulevard with him and he’ll point out 62 of his clients who are immortalized with their own stars on the “Walk of Fame,” stars such as Errol Flynn, Gloria Swanson and Ginger Rogers.

His client list includes some of the biggest names of the 20th century: actresses like Ingrid Bergman, Bette Davis, Natalie Wood and Marilyn Monroe, baseball legends Babe Ruth and Lou Gehrig, and singer Ella Fitzgerald and Billie Holiday.

All have one thing in common besides their greatness, as Roesler explained to correspondent Steve Kroft:: “We’re a business agent for about 250 entertainment, sports, music and historical clients. But most of those are deceased.”

Watch the entire video at the “60 Minutes” site