Here’s a list of the tools that I’m familiar with:
Son of Citation Machine
Citation Machine is an interactive web tool designed to assist high school, college, and university students…
KnightCite Citation Service
Use the publication information provided on the title page (not the cover) of the book.
OttoBib – Free Automatic Bibliography Generator. Fast! MLA, APA …
OttoBib generates bibliographies automatically. OttoBib looks up all information by ISBN for you.
BibMe.org is a new automatic bibliography generator that uses a multitude of web services to auto-fill bibliography info for a works cited page. It then lets you download the bibliography in MLA, APA, or Chicago formats.