Easy Bib http://www.easybib.com
Generate APA or MLA citations for books, book chapters and articles.
Citation Machine http://citationmachine.net/
Fill out a form and generate MLA or APA citations for a variety of common publication types.
Assembling a List of Works Cited in Your Paper http://www.lib.duke.edu/libguide/works_cited.htm
This excellent guide from the Duke University Library demonstrates how to use
APA, Chicago, MLA, and Turabian citation styles for the most common types of
resources.
American
Psychological Association http://www.apastyle.org/styletips.html
The APA website gives some tips about using APA style as well as information
on citing electronic resources.