Domains endings can tell you a lot about a resource
.com - commercial site; company sites
.edu - educational; college or university site
.org - organization or association
.gov - government site; great for stats and reports
Use Google to search for educational, government and organizational websites.
To construct a site search in Google use the following formats:
site:.edu = educational sites
site:.gov = government sites
site:.org = organizational sites
For example:
site:.edu water and pollution
site:.gov uranium mining and Navajo
site:.org macrobiotic diet and sustainable agriculture
Remember - almost anyone can create a website. Information on the web may be biased, undocumented or just plain wrong!
You will need to evaluate web sites for currency, relevancy, authority, accuracy and purpose.