Communication & Mass Media Complete - covers journals dealing with communications, advertising and journalism.
Proquest One Business - one of the largest business databases available to UMaine students, covering all aspects of business, including advertising
New York Times Historical - this database has complete scans of the New York Times, including the advertisements. This is a great source for doing research on the history of print advertising. Click here for a sample screen shot.
Statista - Statista has data from thousands of different sources on many different topics, including marketing data. Detailed reports on advertising trends can be found here, with statistical charts/