Where can I find information on creating a game server. I understand that it is a broad topic, but I am looking for some simple ideas on how to structure it. I program in C/C++. Some links to websites, or books would help.

What's the game like? A game server for a MMORPG and a game server for a board game would be quite different. Also, are you asking about the design of the server-side software, or the machine(s)?

Actually I'm thinking of 2 different design types. 1 is a multiplayer fps and the other would be an mmo. I don't have a game in the works, but I looked at a game like eve online and I'm very interested in how a game server can handle many clients while mediating huge space battles. I don't have a clear perspective on what I'm looking for, since I just started looking into this for the first time. The multiplayer fps is most likely what I would actually attempt to do myself. That might be 2 dozen players at most running around on a level. Regardless of what I go with, this is something I want to build from scratch, so I'm mostly looking into figuring out the best technologies to go with, such as language and libraries.