Citation Builder: One of the best 'free' citation builders available. As of August 2012, it was current for both APA[6th edition] and MLA.[7th edition] It is offered by the North Carolina State University Library. Visit Citation Builder to learn more about this resource.
Microsoft Word 2007/2010: There is a citation feature in Word that is pretty straightforward. Click the References Tab to choose a style and begin documenting sources. Use the help menu if necessary. It isn't really recommended, but many instructors are suggesting students use it to help them format their references & work cited pages. Be aware, it is not current for both APA[uses 5th edition] and MLA.[uses 6th edition].
NoodleBib Express: Nice interface and prompts questions to clarify types of sources. [online journal, database journal, etc.] Looks to be current for both APA[uses 5th edition] and MLA.[uses 6th edition].
Son of Citation Machine: As of August 2012, it was current for both APA[6th edition] and MLA.[7th edition] Visit Son of Citation Machine to learn more about this resource.
Zotero: A free, down-loadable program that allow you to collect, manage, cite and share your resources. Similar to Refworks in that it can manage sources for multiple project thru an account you set up. Best used while you are researching; A little challenging to learn on the fly if you are pressed for time, typing up your references. Visit Zotero.com to learn more about this resource.
From LIS2004 Introduction to Internet Research