Any way to track an IP address from our site?

How do we go about tracking an IP address from a site to a site? We want to add links on our site to another site, and we want to get paid for the referral. How does this work without us forming or joining a specific referral program? Any thoughts?

I like the diagram here, http://click.websitegear.com/, but haven't made my choice yet.

I think dynatracker and spectra are a couple others. Don't quote me on the name thought! I've never used them!

Thanks for the input. After looking at the different links that were posted, I'm thinking that a better question I should be asking is: "How do you decide what type of advertising (affilate or PPC) to place on your site?" I'm starting to wonder if PPC would be a better route to go, considering what we are trying to do. I suppose we can only be affilates of businesses that want affilates and somehow are able to track the incoming leads. Since the majority of people we are looking to refer don't sell a product (i.e. we wouldn't know if a customer bought or not) we would be better doing PPC. ...So much to learn.

Depends on the niche/market, but you could try some of the bigger, more reputable companies, such as, amazon associates, buy, overstock, etc...

These are kind of geared toward a certain mentality and product though. Not sure if that would fit your theme or not.

I think what you really want to know, is which companies have the highest conversion rates on their given widgets. Of course I think this depends on how well their ad cluster fits in with your ui/niche and targets visitors.

I'm curious to see how many prefer ppc vs. affiliate. I don't think there's a "one size fits all" however.

Find a free statistics program for visitors. Something that shows you the unique hits and the unique IP adress of the ones visiting your site. Just copy-and-paste code to your website.

Biggest problem with affiliates/pay-per-sale...

User is at work on computer A. Finds a product he/she likes on your site and decides to buy product. You should get commission. However, he/she remembers site and goes home to check with family about purchase. Ends up purchasing from a home computer and goes direct to the site rather than via yours.

One sale... no commission.

PPC or set fee ads better imo