awhile ago Dean Thevaos posted this tool that would move polygons to a known xy location so long there was an XY field in the polygon attribute table with the x coord and y coord seperated by a comma
it worked in 9.3.1 and no longer works in arcgis 10, anyone know why?
Dim pPolygon As IPolygon
Dim pArea As IArea
Dim pOrigin As IPoint
Dim sXYField As String
Dim dXY() As String
Dim dX As Double
Dim dY As Double
Dim pTransform As ITransform2D
sXYField = [XY]
If (Not IsNull([Shape])) Then
  Set pPolygon = [Shape]
  dXY = Split(sXYField, ",")
  dX = CDbl(dXY(0))
  dY = CDbl(dXY(1))
  If (Not pPolygon.IsEmpty) Then
    Set pArea = pPolygon
    Set pOrigin = pArea.Centroid
    Set pTransform = pPolygon
    dX = dX - pOrigin.X
    dY = dY - pOrigin.Y
    pTransform.Move dX, dY
  End If
End If
__esri_field_calculator_splitter__
pPolygon