There are several sites on the web that can help you cite a variety of sources in a particular style. But citing online sources such as eBooks, database articles, or free web sites can be very challenging. I've found that the clearest examples and information on citing online sources (MLA, APA, Chicago, or CBE style) are listed in:
Online! Citation Styles - by Andrew Harnack & Eugene Kleppinger
Go to Online! Citation Styles, click on a style type such as MLA, then click on "Subscription Service" for examples and explanations of citing articles from library databases. Here's their example of an article from a library database in MLA style:
Maynard, W. Barksdale. "Thoreau's House at Walden." Art Bulletin 81 (1999): 303-25. Academic Search Complete. EBSCOhost. Eastern Kentucky U Lib., Richmond. 19 Nov. 2002 <http://www.ebscohost.com>.
NoodleBib Express offers help with MLA or APA style. Just need one or two quick citations? No need to log in or subscribe -- simply generate them in NoodleBib Express and copy and paste what you need into your document.
Here are the basic pieces of information to collect about a Web page in order to cite its use in a research paper (see also: Online! Citation Styles):
Bureau of Labor Statistics. "Tomorrow's Jobs." Occupational Outlook Handbook. March 7 1996. http://www.bls.gov/oco/oco2003.htm (11 November 1997).