This is a very common problem when doing research online. It's easy to find lots of websites through a quick online search, but knowing which information to trust is the hard part!
In general, follow the CRAAP* method to decide whether or not a website is reputable:
Currency -- Is the information timely?
Relevancy -- Does the information answer your research question.
Authority -- Who is the source of the information?
Accuracy -- Does the information seem reliable, truthful, and correct?
Purpose -- Why does this information exist?
For a more comprehensive explanation of this see MiraCosta College's Intro to Web Evaluation.
*Thanks to the librarians of Cal. State Universitiy, Chico for developing the CRAAP website test!
