Well the interesting and difficult part of the question is you don't have an Internet-connection. Which means you will have great deal of difficulty in downloading and installing a lot of drivers and updates. More than anything (as per my experience with Ubuntu or Linux) you have to have a net connection. And if you have a net-connection then many times you can easily install many utilities via 'synaptic manager'.
As you have asked about how to install softwares. In Linux different utilities have different ways of installation processes. On the top of it, many times you face some problems and have to resolve some issues, while installing a particular s/w. In which case you have to check forums for the solutions.
I suppose you are a novice to Linux (as I am). So try to put up the exact things that you do with your machine. If you are doing something in the terminal, then do post the command that you are giving or the error messages, in case you get any.