Daniel is right, I wasn't paying attention although you will likely also need RefreshActiveView to make the selection visible in your map's data frame...If this is your complete code, looks like you did a good job setting the objects for map, data frame (the 1st one, or only data frame in the map?), and the geometry object. But what is "DOQQImport"? I didn't test the following, but think if you get a reference to this (as Daniel said), this may work (is DOQQImport the exact layer name in the map's TOC?) -- also, I believe in this case the overlap type INTERSECT will give you virtually the same results as COMPLETELY_CONTAINS, so I'd just go with the default:Highlighted in red are the critical changes to your code:
import arcpy
# need a 'handle' on all 3: 'current' mxd, 1st data frame, DOQQ layer
mxd = arcpy.mapping.MapDocument("CURRENT")
df = arcpy.mapping.ListDataFrames(mxd)[0]
DOQQImport = arcpy.mapping.ListLayers(mxd, "DOQQImport", df)
# your geometry object to select by looks fine
myPt = arcpy.Point((df.extent.XMax+df.extent.XMin)/2, (df.extent.YMax+df.extent.YMin)/2)
arcpy.AddMessage("{0} {1}".format(myPt.X, myPt.Y))
myPtGeometry = arcpy.PointGeometry(myPt)
arcpy.AddMessage("{0} {1}".format(myPtGeometry.firstPoint.X, myPtGeometry.firstPoint.Y))
# execute using the fetched layer and defined geom:
arcpy.SelectLayerByLocation_management (DOQQImport, "INTERSECT", myPtGeometry)
arcpy.RefreshActiveView()
arcpy.AddMessage("\nIs this your intended polygon selection result?")
arcpy.AddMessage("(If there are overlapping polys at this location, the result should be a multiple selection.)")
del mxd
Hope that helps, of course test as necessary!Enjoy,Wayne
