It's important to note that there are several paid third-party tools available to assist you in managing GPOs, their scope and effect, and their application, including the following:
FAZAM
FAZAM tracks changes to GPOs, provides version control for GPOs, allows new or changed GPOs to move into production only after being tested and approved, eliminates the risk of making changes to a live production environment, handles multiple users making simultaneous changes, and enhances GPO administration delegation. However, there are reports that this tool does not work well with Windows 2000 and is fully functional only on Windows Server 2003. FAZAM is available at http://www2.fullarmor.com/solutions/group.
NetIQ Group Policy Administrator
NetIQ Group Policy Administrator handles change and release management to keep better track of GPO modification, creation, and deletion, and enhances change simulation and analysis of hypothetical GPO deployments above and beyond what Windows Server 2003 provides. NetIQ Group Policy Administrator is available at http://www.netiq.com/products/gpa/default.asp.
Quest ActiveRoles
Quest ActiveRoles allows junior-level administrators to securely make changes to important elements of Active Directory, including GP. Quest ActiveRoles is available at http://www.quest.com/fastlane/activeroles/.