I currently have purchased a routerboard 112 and an SR9 card (900MHz). I have got the Mini-PCI card installed into the routerboard. I am trying to learn what I need to do to install the software onto the routerboard so that I can make this work. I was told that MikroTik is the only company that is currently making software for the SR9. I am new to this aspect of the wireless world. I would appreciate any help anyone can give.

You have to specify the configuration, that you want to accomplish.
MikroTik RouterOS is pre-installed to RouterBOARD 112, plug SR9 to the bottom RB112 slot and set appropriate configuration.
- search for the the topic 'SR9' in Beta forum, it should help you a lot to setup SR9 card.
- RouterOS configuration options described in the documentation.