PHPMyAdmin is an open source solution that allows you to completely manage a MySQL database from a web-based, PHP-driven interface.
You can obtain the necessary files from http://www.phpmyadmin.net
Last I checked the only file that you have to edit to get things working is 'config.inc.php' , you must include the authentication scheme, the user/pass and the absolute path to the PHPMyAdmin base directory by editing several variables that appear in that file.
If that wasn't what you were looking for, RTM:
A PHP/C-Client/PEAR solution for webmail