Fetch a webpage locally

Well, I need to write a php script to fetch a remote webpage and display it on a local server (provided it meets certain critera). Me and my entire hour of previous PHP experience thought it would be a good idea to take on this task. A simple self-smack on the head taught me that this wasn't as easy as I had planned. Here was my plan: $page = join ('', file ($url)); [ check for 'criteria' here, and if all's well...] echo $page; Naturally, my main problem is that the links and images don't work. (duh!)... So, now I need a way to have the external links re-route back to my script, and alter the <img> tags to reflect the documents new location. Since any of these may or may not be document relative, this has turned into quite a task for me. I'm in over my head... If anyone has done this before, or knows where I can start, please help me. It will be greatly appreciated. :)