On his blog today, Paul has posted this quick guide to working with XML in PHP5, specifically how to parse it and use the data however you'd like.
One of the most common things web coders run into is the need to parse some type of XML file. Many web services return API calls in XML format, so it's just handy to know how to parse these results quickly. With PHP4 you usually have to rely on some large parsing library to get the job done or deal with overly complicated PHP functions, but PHP 5 has a great extension called SimpleXML.
He goes on to give an example, the geocoding service that Yahoo! offers, and two examples of how to parse the response with SimpleXML. He also includes a little bit of extra code to help with some of the more "intricate" XML you might come across.