Heya Rodion - long time no talk. I guess we'll be waging battles not just in CC tournaments, but mafia games as well
1. I guess they do have similarities, but mafia games in CC are much more complex.
2. To put very simply, this is what usually happens:
Day 1 starts - people have a joke vote stage, then go out of it and trying to find someone scummy and in the end usually lynch someone.
Night 1 starts - people send in their actions (both mafia and pro-town roles) and we find a scene on Day 2.
Day 2 - people again pick the scummiest players, discuss and lynch.
Night 2 - rinse and repeat Night 1.
Day 3 - rinse and repeat Day 2.
And so it goes until someone wins.
3. Most of them have pretty much same rules and they don't vary much from game to game.
As far as information goes, just read a couple of older threads - they explain things pretty well. Furthermore, read one of the already finished games (Nostalgia can be a good read, but I'm biased) and try to see what's happening.