Looking for inspiration? Try browsing one of these books for an idea:
Not all web resources are created equal! Only .gov and .edu domains are regulated - which means not just anyone can get one. How do you just get results from these sites? Try a Google Site Search!
Go to http://www.google.com. Type in your search term(s) followed by site:.edu or site:.gov like this:
You can also do this from Google's Advanced Search (http://www.google.com/advanced_search
Books can be a great resource for biographical information on your essay subject. These are some examples - looking for a book about another person? Search for a person in OneSearch.