Bartleby has ENTIRE English books (classics and poetry) you can read on-line for free.
More books are here.
Research
Wikipedia is a great place to go for basic knowledge about a subject. Check the References and Links at the bottom to get more information for trusted sources.
Simple English Wikipedia is great if you want to know more about something in English, but you don't feel confident in your English reading level. The information is good, but the sentences are more simple.
Britannica is one of the best encyclopedias in the world. You can spend a long time here just reading lots of information!
