Thank You, Glad to be of service. Also sounds like you may want to install userpoints.module and setup referal points.
This should help you with your research.
http://drupal.org/project/userpoints

This module provides users with the ability to refer other users to a site they are registered at. When the new users registers, the referral is recorded. Users can see a list of users they referred, and the site admin can view more detailed reports... http://drupal.org/project/referral