Hi Cindy,
If you have a 'click thru' agreement with somebody (Business.com for example) you will pay for the traffic coming to your site, not the results of that traffic.
Track your monthly click thru reports, compare them against your sales results to measure your return on investment. DON'T expect immediate sales from 'click thru' responses, at least not right away.
I suggest you set limits on the monthly click thru amounts (if that option is available) at least until you have established your site well enough to see what kinds of sales conversion results you receive.
I have such an arrangement with Teleplaza.com, Business.com and a couple of others. Business.com shows the most consistent results for the amount charged per month. (No, they don't pay for the referral. :) )
There are a lot of different kinds of 'click thru' programs and you should research them thoroughly.
Good Luck!
Source: http://www.abusinessmentor.com