Gordy, If its something you don't know much about, I would suggest doing a lot of research before hosting it. Because otherwise a support call might be rather difficult for you
Game hosting - this generally uses 400-700MB disk space per game and about 150GB transfer if you have a 16 player game. I would suggest only running these on sturdy servers and only 2-3 games per server.
If you are just supplying the space and transfer you could pretty much just create the account and let the user do it from there. If you are installing the game itself make sure you get familiar with unpacking rars and rpms in linux, and editing the config scripts so they use the right port. Ive set up a few Half-life(mods) and it took me about 30-45 minutes. However since Valve just released whats called Steam Software (like game spy) it might be a little more complicated.
Shoutcast servers..... I wouldnt even waste your time unless you have a 10mbit + burstable server... most streaming audio/video uses 128k rates... that will leave a nice dent in your wallet if you arent too careful.