How to create Site filters based off of manually created sites

If you have chosen to create your sites and subnets manually instead of importing them from AD, what is the easiest way to create filters that contain the computers associated with those sites?

The following query is one way of achieving this goal (another method would be to target the actual subnets contained in each site):

  SELECT ip._ResourceGuid
  FROM Inv_AeX_AC_TCPIP ip
  JOIN vSubnet sub ON sub.Subnet = ip.Subnet
  JOIN vSiteSubnetMap map ON map.SubnetGuid = sub.[Guid]
  JOIN vSite s ON s.[Guid] = map._ResourceGuid
  WHERE s.Name = 'name of site'