This episode explains how to avoid plagiarism in your writing. Below are further links to resources which would help you become a more effective writer.

Plagiarism: What It is and How to Recognize and Avoid It
http://www.indiana.edu/~wts/pamphlets/plagiarism.shtml

Avoiding Plagiarism
http://owl.english.purdue.edu/owl/resource/589/01/

Plagiarism
http://www.unc.edu/depts/wcweb/handouts/plagiarism.html