>Is there any way to find a location DLL was registred from?
Locate the CLSID (under the ProgID if you don't know it to start) and then check the subkey for the CLSID containing the InProcServer32 entry, which names the host. Note that out-of-process servers (.EXEs) do not have this entry, and you may be referered to another file type than a .DLL such as an .OCX