Here at Norris Medical Library, Univ. of So. Calif., we also catalog CD-ROMS
as computer files with accompanying manuals.  When we do holdings information
for our Geac opac, we input separate holdings records for each accompanying
manual, using the call number that has been assigned along with an added:
[guide] or [manual] or [ref. manual], or however it is called by the
producer.  We often also put a 505 contents note for the accompanying manuals
to describe them more explicitly (particularly if there are more than 2).
Maggie Freed
Head, Bibliographic Management