In order to get the Ubuntu VM created on a OEL machine, please follow the steps given in the following links with some changes as stated in this document. This document will point to the correct commands and files as seen on OEL/RedHat.
First follow the steps given here.

Remember that you need root privileges for executing most of the commands. So simply "sudo root" and then follow through the steps as given. Following are some changes that you will need to do to make the commands work on OEL. If not stated here, the commands should work as is as stated in the Ubuntu doc.

1.1 Become a sudoer

Once you are "root", you do not need to execute step 1.1 (become a sudoer).

2.2 KVM installation

Remove "sudo" from all the commands.
Replace "apt-get" with "yum".

run the following command :

yum install qemu-kvm libvirt-bin ubuntu-vm-builder bridge-utils

yum install virt-manager

After the Reboot, the libvirtd daemon is supposed to start automatically. But I have seen instances when it has not started by itself. In that case, I have manually started it as follows :

cd /etc/init.d
./libvirtd start

2.3.1 Desktop

Install bridge configuration
Again, remove "sudo". The name/location of the networking file in OEL is /etc/rc.local.
Edit that file as follows :

gedit /etc/rc.local

Add the setting as given in the Ubuntu doc.

For Restarting the network:

cd /etc/init.d
./network restart

Next follow the steps given for Templating.