what kind of drive?
since its an older machine, im assuming its standard IDE stuff.. no raid or sata or firewire.. correct?
if so, just plug in the drive as a slave drive on prim/secondary (whatever you decide) IDE connection and boot up the computer.
if this is the 2nd drive in the system, it will most likely be known as /dev/hdb to the system.
run 'cfdisk /dev/hdb' as root from a terminal/console. read the man page about it if you need some info about it.
it will bring up a nice and easy UI which is pretty self explanatory. create a partition on the drive of whatever size you want. then set the type for the drive.. will you be writting to it from windows? if so youll need it to be FAT32.. if it has nothing to do with windows, reiserfs should work just fine. then 'write' the changes to disk.
create a folder for where to mount this drive, as root, ie 'mkdir /mnt/music'
then edit your /etc/fstab file, as root, add this line, and save.
Code:
/dev/hdb1 /mnt/music reiserfs auto,users,umask=000,rw 0 0
now type 'mount /mnt/music'. it should now be mounted fine, and will be whenever computer is booted. g'luck
edit: for the program your using, either edit its configuration so it looks where you have your music mounted, or mount it to where it looks (ie /var/whateverYouSaid..)