2008 Active Directory has new GPOs for managing local accounts.  You either attached a new GPO to the root of the domain with the changes.  Or if you want different sets for different departments you can link the new GPO to the specific OU.  The settings you will need are found in the Group Policy Preferences.  More about that can be found here:

http://blogs.technet.com/b/askds/archive/2007/11/28/introducing-group-policy-preferences.aspx

Alternatively you can use powershell scripts to accomplish this.  You would need to cater the script to a list of hosts and have local admin rights to the systems.