grab user data through casetracker/CCK

All of my casetracker projects have external links to the actual project files. I need those external links to include the Drupal project ID, group ID, and user ID...and using the CCK I've been able to append the group and project ID's to the external URL's automatically. However the user ID has proven to be a serious issue...I can't get to it. I've tried echoing a series of variables, but nothing seems to give it to me. Is there a way to access the User ID through the casetracker so that I can use the CCK to append it to my URL's???

Thanks for the help,
EPeay