Being an affiliate is not difficult at all. If you plan to make any money out of it it'll take a lot of effort but its generally free. The idea is that the company actually selling the goods or services wouldn't have got the sale without your intervention thus you get compensated on an agreed upon basis.

These programs do vary vastly from what i've gathered this far, commissions range from anywhere around 4% up to around 75%!!! I guess it just depends what they're selling and how good you might be at selling it.

If you have a large number of friends on Facebook, or a huge e-mail list, or if you're just good at attracting lots of visitors to a site or blog you've created... I'm sure some of those people might be interested in buying something online anyway, if you mention that you're their personal one stop shop and that they can just e-mail you what they're looking for and you'll organise it... Then you just go your your affiliate partner search for the requested item and copy the link for your friend. And working with quality companies like Amazon.com, Kalahari.net and ClickBank.com you cant go far wrong with service! It could be a possible goldmine for you and there are thousands of things to sell!!