EasyBib (Library Subscription): Save and create bibliographies; integration with WorldCat
Owl Writing Lab - MLA Guide: Excellent site; it's become a standard resource for students.
The library (of course) also owns multiple copies of the print MLA guide:
Gibaldi, Joseph, and Modern Language Association of America.,. MLA Handbook for Writers of Research Papers. New York: Modern Language Association of America, 2009. Print.