You can order your free Ubuntu CDs from http://shipit.ubuntu.com. By default Ubuntu comes with Gnome desktop environment. If you are an absolute beginner to Linux I would highly recommend Ubuntu. Other wise you can also order free CDs for Ubuntu’s K desktop environment Kubuntu, from http://shipit.kubuntu.org.
Remember these CDs will take atleast 4 to six weaks to arrive. You can get Ubuntu quickly if you order your CDs from Linux Pakistan (Rs. 35 only + shipping charges). Feel free to contact Tariq Farooqi for any questions, information or details.
There are many other ways to get Ubuntu CDs. Check out your local computer hardware and software stores and shops. Contact Pakistan Linux User Community members in your town if any one of them has spare Ubuntu CDs they would love to help you. I am one of the PLUC members so feel free to contact me if you are in Karachi.