I'm sure that most of you know about what resources the library has to offer for online research, but here are some of my favorites you might try if you're still casting about for some options:
JSTOR: General purpose database with articles in pdf format. Consider restricting your search field to Philosophy and general science or target other fields as needed.
The Philosopher's Index: Just philosophy. Some articles will be available; others will not (depends on our library's subscriptions). It's usually best to use this on campus so you don't have to deal with the proxy server which can sometimes impede efficient access to articles.
The Stanford Encyclopedia of Philosophy: Great general background on many philosophical topics. Good source of references for other articles/books to examine.
Google Scholar: VERY general search. Search for UI's library in the advanced preferences to enable a nice article linker to get full text when you can.
Remember: the first essay does not need to be a long research essay. I'll be looking for careful argumentation; but that may concern just one source that we've already read if that's what is needed for you to support your thesis. I'm of course happy for your essay to draw upon other sources: depending on the topic you choose, you might need to.