I'm trying to set up a local server for friends for a lan party and I've been looking everywhere and I can't find crap for how to do it on linux. Any help would be appreciated.
Ignore the haters telling you to switch to Windows: Linux is perfect for hosting servers. Before I link you to a guide, or write one, what distro is your server running?
Honestly, Linux is the way to go. Most website publishing services use Linux as the key feature for running websites. I'm 99.9% that the red guy uses Linux to host this website and the servers this community has today. To be honest with you, when I was starting to make servers back in the day I used Windows and let me tell you, Windows itself takes way to many of the ram just to run... windows, then I switched over to Linux and my servers ran way much better. Like a 2% boost than before. I would agree with @Sticky Bandit statement on how Linux is good for hosting servers and disagree on Trinity statement.
This will get you started. I would suggest automating the server start and stop with some script, and get some sort of "crash catcher", so whenever the server crashes it will automatically restart. Use http://ttt.badking.net/ to get any additional information, like configs and helpful commands.