By all means, use Google and the open web.
However, be very discriminating about what resources you use. Some freely accessible resources are far better than others.
This guide from the Colorado Community Colleges provides a good explanation about how to evaluate websites:
Much information that you need will not be easily available on the web, however. Learn how to use the library resources in the remainder of this guide!
Regarding Wikipedia, see the Wikipedia article titled Reliability of Wikipedia.