I entered ninjitsu a few months ago and we learn a lot of rolling, self defence and stuff like that. The only thing I can say is that my teacher always told me to look at the opponent's face and not the hands or legs. Oh, and try to distract your opponents during a fight. My teacher's favourite style is to snap his fingers or clap at a different direction from where the opponent is looking and when the opponent is distracted he'd beat the poor guy up senseless =D

Hope I've been helpful