In addition to your textbooks for the course, the following links provide information and advice you may find helpful as you write your papers:
The Purdue OWL is a handy resource if you have questions about MLA style, mechanics, writing genres, or pretty much any other writing issue you might encounter.
If you have any questions about appropriate citation or what constitutes plagiarism, start with this guide. If that doesn't answer you questions, consult your instructor or make an appointment at the Writing Center. Remember, you're responsible for familiarizing yourself with the conventions and expectations surrounding plagiarism. Ignorance is not an excuse, and plagiarism can be an Honor System violation.
The Writing Center is a fantastic resource at any stage in the writing process. It's always beneficial to get a fresh set of eyes on your writing.
Some of this guide won't be relevant (like the guide to finding sources in the Harvard library), but most of it will be. This guide is well-organized, detailed and comprehensive.