Lost Disk Space Ubuntu 9.04...

I am running ubuntu 9.4
I notice my disk has been running out of space fast.
I have used all clean-up tools available to my knowledge. autoclean, clean, bleachbit, computer janitor, etc.
I have forced a fsck " sudo shutdown -rF"
I have about 60G of space I cannot account for.

enrique@Ricky-desktop:/$ df -h
Filesystem Size Used Avail Use% Mounted on
/dev/sda1 72G 65G 4.1G 95% /
tmpfs 248M 0 248M 0% /lib/init/rw
varrun 248M 352K 248M 1% /var/run
varlock 248M 0 248M 0% /var/lock
udev 248M 140K 248M 1% /dev
tmpfs 248M 88K 248M 1% /dev/shm
lrm 248M 2.2M 246M 1% /lib/modules/2.6.28-13-generic/volatile
enrique@Ricky-desktop:/$ discus
Mount Total Used Avail Prcnt Graph
/ 71.93 GB 64.25 GB 7.67 GB 89.3% [*********-]
+ib/init/rw 247.9 MB 0 KB 247.9 MB 0.0% [----------]
/sys 0 KB 0 KB 0 KB 0.0% [----------]
/var/run 247.9 MB 352 KB 247.6 MB 0.1% [----------]
/var/lock 247.9 MB 0 KB 247.9 MB 0.0% [----------]
/dev 247.9 MB 140 KB 247.8 MB 0.1% [----------]
/dev/shm 247.9 MB 88 KB 247.9 MB 0.0% [----------]
+onnections 0 KB 0 KB 0 KB 0.0% [----------]
+c/volatile 247.9 MB 2.1 MB 245.8 MB 0.9% [----------]
+l/security 0 KB 0 KB 0 KB 0.0% [----------]
+infmt_misc 0 KB 0 KB 0 KB 0.0% [----------]
+ique/.gvfs 0 KB 0 KB 0 KB 0.0% [----------]
enrique@Ricky-desktop:/$

Where is this lost space?

Please help.