I've been thinking of tackling another project for the sake of learning.

This code will essentially track information on websites with a code that is voluntarily installed by the webmaster. I've been trying to think of the best way to get this information back to my database, though. I started looking around, trying to find the best way to do accomplish something like this, and I've noticed that many people use iframes to do it. I'm not too fond of iframes (although I used to love iframes and frames back in the day ), so what other good ways do you know of to accomplish this?

What type of information are you talking about? AJAX sounds like a viable option.

Ah, AJAX - the language I've yet to learn.

The main purpose of doing this code is to learn how. I figure something like this can teach me many important coding lessons along the way and would be a very important project for me. The type of information I want to gather is, so far, undecided. To start with, I'm thinking maybe just number of page loads, visitor ip addresses, region of the world they're in, other basic stuff like that.

You may want to look into "tracking systems" because there are a few of them that do some of the things you're talking about. Some things that might be of interest to you while doing a little project like this:

-PHP : cURL
-GeoIP

Awesome, those are two things I've yet to do, but exactly the kind of stuff I intend to learn with this project. Thank you very much.