This isn’t really an answer to your question, but one of the ways to quickly find stolen content is to work unique phrases into your work that can be searched for with “unique phrase here”. Both of the recommendations by croupier are sound, but the problem with much stolen content is the people who are stealing it are hard, if not impossible, to bring legal action against. On the other hand, especially where forums are involved, content is often posted and the forum owner doesn’t know it is stolen. I have had this happen to some of my writing and once the forum owners were contacted, they fixed it. There will always be people who would rather steal than do their own work. One area that you can use, as the Professor mentioned, is become actively involved on some forums. If you prove yourself to be trustworthy, you will have a few places to start bashing the thieves when it happens to you.