There is a lot of good information on the World Wide Web, but there is also a lot of misinformation. How can you tell the difference? There are many excellent guides to help you evaluate resources you find online. The following are a few sites to get you started:
Evaluating Web Pages: Techniques to Apply & Questions to Ask is an excellent and comprehensive guide from the University of California Berkeley Library.
Evaluating Web Sites from Ohio State University Libraries provides a tutorial to familiarize you with the process of critically analyzing web resources.