OO PHP/MySQL and XML for webservices

I am writing object oriented PHP to output an array from my MySQL database to an XML file that I use as meta data that connects to my web application. I can send data to and from the web application using OO PHP and/or XML, but I am sure better ways exist to do this and I am looking for anyone that is using web services that is willing to share knowledge as I am also willing to do so.

I want to share development styles and improve my own. I am willing to also help anyone else.