OVERVIEW:
This is a simple way to retrive contacts from Gmail or a hosted application from Google with PHP. This script uses curl to make requests to Google Contacts Data API. 
More information about Google Contacts Data API can be found at:
http://code.google.com/apis/contacts/docs/3.0/developers_guide_protocol.html

WHAT YOU NEED:
PHP with curl enabled.

HOW TO USE:
Just replace the http://domain.com/google.php with your domain name and script path, upload the file and then click on "Authorize with GOOGLE", the user will be redirected
to Google's Account page where after logging in will get back to your page and list the contact's name and email address.

TODO:
-add validations (in case no token is sent to google)
-check if the tokens are valid
-show message if user has no contacts