This is definately possible (and it's not too hard either
Please note: you do not need seperate partitions for /var and /home. I personally have never made them seperate. But if you still want to:
Use the tool fdisk (or cfdisk) and make the partitions from the unallocated space. Then, edit your (make sure you have superuser privledges) /etc/fstab file to mount /home and /var as your new partitions. By looking at the other entries already in fstab, this should be fairly self-explanatory. By the way, fstab is the File System TABle.
I have never done this, but I have set up a few Linux computers and run RH9 on my notebook as well, so it should work.
Come back here for any more questions!