Help Managing Site PHP
 

I'm trying to setup a site in PHP, and I would like to try and organize the information (the info is at least in HTML)... like when you click on links to get some kind of info, the url comes up as index.php?id=920 or something like that. How can I make it do that? And when that's setup, is there anyway to have it so that I can edit a file (or a few) to change the whole look of the site without having to change every single file for id=920 and so on? I've been looking at some PHP tutorials and I don't really see what I want. And I don't need a portal cause I don't need extra stuff like a calander and what not and it has to cover the whole site as I'll be adding scripts to it later on... I just need something simple, yet extensive. Can anyone help me?