In tip 3509, I discussed another way to locate FSMO role holders.
In Knowledge Base article Q223346, Microsoft discusses the the placement and optimization of domain controllers. Here is an excerpt from the introduction:
"Windows 2000 domain controllers support multi-master updates for the replication of objects (such as user and computer accounts) in the Active Directory. In a multi-master model, objects and their properties can originate on any domain controller in the domain and become "authoritative" with replication.
Certain domain and enterprise-wide operations not well suited to multi-master placement reside on a single domain controller in the domain or forest. The advantage of single-master operation is to prevent the introduction of conflicts while an operation master is offline, rather than introducing potential conflicts and having to resolve them later. Having a single-operation master means, however, that the FSMO role owner must be available when dependent activities in the domain or enterprise take place, or to make directory changes associated with that role.
The Active Directory defines five FSMO roles: schema master, domain master, RID master, PDC emulator, and infrastructure. The schema master and domain naming master are per-forest roles. The remaining three, RID master, PDC emulator, and infrastructure master, are per-domain roles.
A forest with one domain has five roles. Every additional domain in the forest adds three domain-wide roles. The number of FSMO roles in a forest and potential FSMO role owners can be determined using the formula ((Number of domains * 3)+2)."