Shark27 - 6:51 pm on May 3, 2011 (gmt 0)

"Avoid making it obvious to your competitors that you are buying links. I was able to create a Google alert that told me about each new site in a network that my competitor was buying into. As soon as a link to my competitor pops up on a new site in this network, I report paid links to Google. When I do so I show that it is far more than my competition involved in buying links."

I don't understand how you can tell someone is paying for links? If a site suddenly links out to your competitor, you're just assuming it's paid? Or are these links coming from obvious link farms?