How would I go about starting a server?

Do I need to pay additional $$$ for some kind of hosting for my Server? I am really dumbfounded on how the internet really works in terms of servers how they connect to the web to get a site. I really don't want to start a web site, I just want to know how in case I want to start my own. I am in tremendous need of knowledge.
Thanks in advance,
Steven T.

You can pay a place on a big line to let you put their server inside their building on their big line. Thats called colocation. Its usually relatively expensive as far as what an individual might want to spend.

Alternatively if your internet connection at home is fast enough and the user agreement with your ISP allows it. You could run a small web or game server from that connection.. Obviously you require a static IP or a dynamic DNS service such as NOIP.com

depends, what do you want to host? game servers are no biggie. but like said above, you need a static IP.

some times when my geocities is down for maintenence, i use my old POS 400mhz as a webserver. not real fast, but it gets the job done.

If your doing ftp, web, etc, best bet is get linux or BSD.