The Chicago Manual of Style (online). 16th ed. Chicago: U of Chicago, 2010. ;(Olin Reference Desk Z 253 U69x 2010) "A standard work, thoroughly revised and updated, which serves as a how-to book for authors and editors. The basics online: Chicago Manual of Style.
MLA Style (MLA's web site)
Provides some FAQ's; however, this site does not provide the full style manual online.