Building traffic organically (i.e., not paying for it with money) is easy, but it takes some time. So what you save in time, you spend in dollars and vice versa. It's very easy to get suckered into spending too much money for traffic. Sites like Google makes the majority of their revenue through advertising just like thas that their users pay for. I know it can work but it's very difficult getting enough knowledge before you go broke.
That's why a lot of online entrepreneurs build free, "organic" traffic, depending on referrals from search engines and other sites.
I'll try to bring you regular installments on how to build traffic on the cheap and how to leverage that traffic from "shoppers" to "buyers."