Look at the resources detailed on the library's Media Industry research guide.

For TV ratings, use TV By The Numbers.

For ratings and market share from 1987-present, take a look at the International Television & Video Almanac HE8698 I55, available in Annenberg Library Reference.

Go to Variety for box office charts, etc.

For data on Broadway weekly grosses and attendance, going back to 1984, see The Broadway League (scroll down the page). There are also seasonal statistics available for New York and touring companies.