not sure if this technique works on NURBS. im sure it does.

but for polygons >

to create a hole. Create a cyclinder to the size u want. place it in the position on the geometry u want the hole. (make sure its right in)

Then select the geometry, shift select the cyclinder. then go to

polygons > booleans > difference

however u may have problems when smoothing, so although this is the easiest technique, i wouldnt recommend unless your not smoothing it


hope this helps