Are you sure, you've done this before? /mnt is not the command which mounts a volume, it is the mount
point. You also don't need to mount the shares on your Linux machine, as I think you want the Linux machine to be your server.
I would suggest you take a look at
Samba By Example, also available as .pdf.
However OS9
cannot access Windows shares by itself, you will need to get an extra software, OS X will work fine (since it also uses samba). So you have to either switch to OS X completely or buy extra software or use
netatalk which should be included in your Linux distro as well.