Quoted from Coyote:You're gonna have a real hard time finding anything 'free' that will 'auto-place' components.
You can try DipTrace, there's a free version of that, with a not-too-steep learning curve. But you're in for a long ride, if this is your first shot.
DipTrace is the best I've found, but the free version has a limit on how many traces you can run which may be a problem.
An interactive schematic viewer like astyy describes would be really cool, but I don't know of anything like that existing. Current schematics for games are definitely limited by trying to fit on single sheets of paper causing you to have to page back and forth a ton sometimes.