I recently bought somethings from J-List and I did not pay not even one cent. I use the store credit made from the Affiliate program that I'm part of. For those who don't know what an affiliate is or how it works, here is a link to Wikipedia, it is too long to be explained here and there are different types of affiliates.
Since it was my first time using my credit, I only bought something small. If you are wondering, most affiliate programs give you the option of getting your payment in store credit or real money. However, if you choose real money, you are going to get less of a profit. Most big online stores have affiliates and you if you want to get one, you must apply and wait to be approved.
When I see a blog that has an affiliate link, I remember to visit it when I going buy something. So, have you applied for any affiliates and do you visit any?