MLA Literary Research Guide Online
The Literary Research Guide (edited by James Harner) is a selective, annotated guide to reference sources essential to the study of British literature, literatures of the United States, other literatures in English, and related topics. It contains over 1,000 entries, including electronic resources, and is updated regularly. It includes information about internet sources, biographical sources, bibliographies, dissertations, etc. It mostly includes sources related to literature written in English, but there's a Comparative Literature section as well as other literature-related topics, such as the performing arts. It was previously available only in print, but there is now an online version. You can find it on the English Subject Guide under the Reference tab. Here's a direct link.