Although this came out late last year, I just bumped into it recently, and it provides a neat way to manage contact lists for OCS 2007.
Description of the free tool from their website, slightly updated for grammar:
OCSCM Beta enables the IT administrator to manage operations related to OCS users:
1. Ability to create OCS users (Active Directory user with live communication server option Enable).
2. Assign & re-assign contacts list for an OCS user.
3. Delete any contact from all OCS users' contact list.
4. Send notification mail to all contacts about a new OCS user.