For more help using the MLA style, these books are great reference resources:
The Purdue OWL offers sample annotations (in MLA Style!) to help you with writing your annotated bibliography.
Check out how to create an annotated bibliography fomatted in MLA style, from the people who created it.
Modern Language Association provides a helpful (but brief) list of questions and answers:
Frequently Asked Questions about the MLA style
Here is another great resource for information on any style-related questions:
The Writer's Handbook MLA Documentation Guide - created by the University of Wisconsin (Madison)
"2009-0604-19-SeattleCentralLibrary" by Bobak Ha'Eri - Own work. Licensed under CC BY 3.0 via Wikimedia Commons.