I don't know any tutorials, but I can give you one way to go about doing it.

Use their animation. If the player is at the end of a punch animation, the opponent checks his distance. If he is in range, he checks his own animation. If he is blocking, he runs his block animation, if not, he takes the hit.

So right there you see that at least with the player, you'd be setting up stances, checking to see what stance the player is in, what stance the opponent is in and how certain hits are delivered by what stance/move both players are in.