It's not uncommon that popular sites are often plagiarized word for word. It's probably happened to you, as much as it has to us. You might find tools like CopyScape offer some useful automated tracking but it's limited in scope. If you're looking for more, consider Tynt.com's Tracer (Beta).
What does Tracer tell you? The Dashboard gives you a tag cloud of the most copied words, a list of the most copied images and pages, as well as high-level stats for page views, copies, etc. over different time spans.
Digital marketing executive with proven experience in all aspects of search engine optimization (SEO), performance-based advertising, consumer-generated/social media, email marketing, lead generation, Web design, usability, and analytics. - 20-year Internet marketing veteran, currently serving as the Digital Marketing Campaign Manager at Antenna Group (formerly Chicago Digital). - Former Editor-In-Chief of Website Magazine, and a regular speaker on Web technology digital marketing strategy - Author of several books on digital marketing Including Web 360: The Fundamentals of Web Success; Affiliate 360: The Fundamentals of Performance Marketing; Domains 360: The Fundamentals of Buying & Selling Domain Names, and SEO 360: The Fundamentals of Search Engine Optimization.