file upload using CCK not showing nid reference
So lets say you have a content type X. You add a field Y to X to upload a file (using filefield or image etc) then you will find the nid and fid in the field table created by cck. 
This table will be something like content_field_Y which should have the nid and fid that you desire.

Update: To clarify the column name will not be simply fid, but will be the machine name of the field suffixed with _value, _nid etc.