Before using any information you should critically evaluate source, especially if it is from a website.  

Ask yourself:

Who?  Who wrote this information and how much authority does this person or organization have? Why should I trust him or her? Does the person have a bias?

What? What is the content of this source about? Is it relevant to my research question?

When? How current is this information? Does currency matter for my topic?

Where? Where did the author get his or her information? Are sources cited? Is the site sponsored by an organization that might have a bias?

Why? What is the purpose of the resource? Is it to entertain? Inform? Persuade? How does this purpose match your own?

Be sure to ask a librarian if you're still unsure if a website or article is appropriate for your research.