Online Writing Lab (OWL) at Excelsior College - Provides a helpful introduction to common elements of MLA style with examples for in-text and Works Cited citations, an MLA checklist, and demo. Scroll down and find the MLA options on the left-hand menu. The OWL at Excelsior College also has excellent guidance for the writing and research process.
MLA Handbook by 
Oxford Paperback Thesaurus
Oxford Dictionary of Quotations
The Oxford Dictionary of American Usage and Style