Purdue OWL Writing Lab--MLA format and Style Guide: General Style Guide
Purdue OWL Writing Lab -- MLA Format and Style Guide: Creating a Reference List
You can also watch the Purdue OWL MLA vidcast series.
http://www.citationmachine.net/
Do not rely on a citation generator to always cite an item correctly. Always double check the generated citation against the APA handbook's latest rules and guidelines.