Weeks ago when I was trying to setup Ubuntu in my pc for the first time, installing new software you need in your new pc would be a impossible process without internet or any Repository DVDs. I managed to get a few resources from net and here I will explain it as a step by step procedure. First you should have another computer which is well connected to the internet or you should have an APTonCD created by someone. Once you install the required softwares with the help of internet connected PC, you could backup all the packages into a CD for using next time.