Finding contemporary news about and reviews of musicals is one of the best ways to see how they were received when they were first produced, along with any revivals, or films that they are connected to. The New York Times is a great place to start because it has very robust theater reporting and will review most shows premiering in New York both on and off Broadway.
Searchable access to the New York Times (Late Eastern Edition), in full digitized page images.
The Performing Arts Periodical database contains popular, industry, and some scholarly publications related to theater, dance, and music. Title include Variety, Rolling Stone, and The Stage, and many will have news about shows in production as well as interviews and reviews with performers and creators.
Publications created by and for specific minority groups may have different perspectives on a musical or play than the main stream press. For example, Dreamgirls was not reviewed favorably in many publications when it premiered in 1981, but publications like Ebony were more favorable towards it and commented on the coverage by other press. Ethnic NewsWatch is a database that focuses on news sources created by and for minority and ethnic groups.
Magazines, journals, and newspapers of various ethnic groups in the United States.
The following websites are good sources for news about what is happening on Broadway, though they may not contain much historical content and their search options are not very robust.
University of Michigan-Flint