I'm a person who enjoys the sport of fighting, BUT I would never advise instigating for the sake of it...especially out in public =\.
Now that being said, I know intimately what it's like to want to fight and to see where you stand. I'm (admittedly) hot-headed irish stock and I feel best just after I've done a session of ground and pound or put someone in an arm bar.
Fighting for protection, confidence, strength...these are great goals, and a natural outlet. I second the thought of training with friends or a gym. I think a lot of people have 'fight' in them (a natural drive, aggressiveness)...and having that desire can fuel some positive training and mental discipline.
An MMA gym will teach you:
-footwork, head, and body movement
-effective striking tecniques: elbows, knees, straight punches, hooks, overhands, uppercuts, kicks, stomps, and so on...
-clinch work: controlling someone's body weight to issue powerful strikes or to get them to the ground
-ground striking: maximizing the mount, back and side positions
-jujitsu: guards, passing guards, defending passes and submissions, submitting via arm bars, triangles, kimuras, knee bars, guillotine choke, rear naked choke, and many more
-misc: confidence, conditioning, endurance, explosive power, breathing techniques, vs 1 or multiple opponents
If you're interested in training for good aims, I'll be happy to share more or help you gauge a gym locally.