Scholarly handbooks and companions are an excellent starting point for your research. They provide thorough overviews of the main issues and questions in a given research field, and are often written by leading scholars. They are also useful to get a sense of the range of recent scholarship in a field.
Credo Reference Unlimited: Contains a number of theater encyclopedias and dictionaries.
Literature Resource Center: Provides access to biographies, bibliographies and critical analyses of authors from every age and literary discipline. Includes articles from Contemporary Authors, Contemporary Literary Criticism, Dictionary of Literary Biography, and much more."Authors by type" searches may be limited to genres such as "domestic dramas," "dramatic monologues," "Elizabethan drama," and other dramatic themes.
Dramatist's Play Service: Complete Catalog of Plays. Provides acting editions of plays and assists with licensing of performances.
Play Index: Provides citations to plays published individually or in collections from 1949 to date. Covers wide range of plays written in or translated into English, including one-act plays, pageants, plays in verse, radio or television plays, and classic drama.
Playbill Online: Theatre news, listings, and some reference including awards.