If you're feeling adventurous you can install KVM-66 (April 2008) from the testing repo. I have to warn you though that it's in testing for a reason. Also even though this is drastically newer than 36 it's still 6 months old.
yum install --disablerepo=\* --enablerepo=c5-testing kvm kmod-kvm
yum install qemu
As a side note there is no PAE version of the KVM-66 in the testing repo which definately limits usefullness.
3. We need to load the KVM kernel module now. Which module you load depends on who made your CPU.
If you have an Intel CPU do this
modprobe kvm-intel
But if you have an AMD cpu do this
modprobe kvm-amd
Verify that the kernel module loaded properly by using lsmod.
/sbin/lsmod | grep kvm
Add the user that will be managing kvm to the kvm group
usermod -G kvm -a grant
4. Change permissions on the kvm devices. You won't need to do this if you reboot before using it.
chown root:kvm /dev/kvm
chmod 0660 /dev/kvm
5. Creating your virtual hard drive
Since we installed qemu we can use the qemu-img command to create a virtual disk of 5 GB. This is in the Copy on Write format which is very useful
qemu-img create -f qcow2 Centdisk.img 10G
You can use dd to create a sparse file as well
dd if=/dev/zero of=Centdisk.img count=1 seek=10G
Either of these will create a disk file that will go up to 10GB but not consume the space on the drive until it's filled. Using qemu-img is probably the better way though.
6. Install an OS
qemu-kvm -hda Centdisk.img -cdrom CentOS5.2.iso -m 512 -boot d
This tells kvm to use the 10GB disk we just created and use a .iso file as if it were inserted into the cdrom as well as boot from it. Memory is set to 512 MB.
7. Boot our OS
qemu-kvm -hda Centdisk.img
If all goes well you should see your newly installed OS boot up.