I've been googling and yahoo'ing and posting on various webmaster boards for a few days now and I can't find a solution to my problem.

Basically, I need to load an external page as iframe src and then log the content of the iframe, which is output as a single line of text. The external page needs to see the visitors ip address rather than my own web server's address. What I'm trying to do can't be done using a static IP proxy. The external page needs to be loaded from each individual visitor's IP address and have the content logged into a file on my web server. I hope all of that made sense. If not, ask for more info.

I would be willing to Paypal someone a couple bucks to contact me with a working solution.

It isn't going to happen.
The server supplying the iframe content would "see" the client IP because the iframe is a client side request, Your server has absolutely no involvement other than serving the page that has the iframe defined.

BUT there is no way at all that you can request the content of a external source in the browser and send it to your server. It would be blocked as a XSS (cross site scripting) attempt.