Whether you realize it or not, if you've been on the Internet today, you have encountered affiliate marketing. If you have ever “clicked thru” one site to order something from another, the first site probably received a portion of the sale. For instance, independent booksellers have limited shelf space for books. But they can offer their customers an almost unlimited inventory of titles by affiliating with companies like Amazon or Powell's. The more orders, the bigger the affiliate percentage.Vi.