I would have one partner create a separate page/contact form specifically for the advertiser – so only people who see that contact form are people who were referred to by the advertiser. The advertiser would use that page as their outbound link. I know you can track outbound clicks in Google Analytics events and Contact Form conversions (usually through most contact form plugins) but that is the best way I think. Never done it, but this is how I see most affiliate programs like that work.
Be sure to check what kind of customer support you can expect from your affiliate program once you have signed up. Do your research online and if possible, speak to other sellers using the program to get their thoughts. Can you speak to someone via phone or Skype or do you have to wait 72 hours for email responses? Be clear on this because trust me, you will need support at one point or another.
Diane, leave valuable comments on other blogs (preferably dofollow and commentluv blogs), become active in forums where you can leave your websites link in your signature, maybe try http://www.linkreferral.com for a while, to get your visitors up. Just keep link building and interacting, and you will get there. But you need to be patient. I wouldn’t buy traffic.
I do make a small commission on some of the products and services that I use and recommend through affiliate relationships with those merchants. Before making any purchase you should always rely on your own judgement and do your own due diligence. The results you get will be entirely based on your own experience and skill set. Never, EVER purchase anything that you cannot afford. Avoid purchasing products that do not have a clearly stated Guarantee, or that promise ridiculous results, like "Getting Rich Quick". There is no guarantee that you will have the same success with any of the products or services recommended. Most people don't do anything with the products they buy, and most of the time, their results are zero! My results aren't typical because I'm not typical ;-)
The amount of money you can make can depend greatly of you budget. If you have a small budget and you don´t have a lot of money, then you have to start with free marketing methods like article writing, blogging, forum marketing and such. It takes a lot more effort ant time to have success with these methods. But they are very effective if you keep writing articles and participate in forums. You can make $100 a day within just a few months just with article marketing.