EasyBib is a free bibliography and citation maker. The free version allows you or students full access to their autocite management tools, and to export to Microsoft Word. MLA style is free for users, but if you need APA or Chicago/Turabian styles you will have to purchase the school or librarian editions. The school editions give educators lots of useful benefits and options. Try EasyBib for IPhone/IPod/IPad where you can just scan the barcode to generate the citation.