you can export your outlook contacts to a comma-separated text file (CSV) i believe.
with phpMyAdmin, you can import CSV files. You must first create a table that matches the format in your CSV file with fields of the appropriate type to store the information.
if you are wondering how to get PHP to add items to your outlook, i think you are out of luck....you'll need to write an application for your local pc that you can call from a web page...java? activeX?
same is true for vice versa...php to get a single item from your outlook file...either you deal with exporting CSV files or you write some kind of custom application that runs on your desktop machine.