It's like Woody Allen said, "Don't knock masturbation. It's sex with someone you love!"
Okay, so as for "wresting the power"... Just show up to public meetings (any kind where they are voting on legislation, unfortunately you can't do anything about the court system's decisions!) and pay close attention. The law makers are acting on behalf of all of the residents to whatever area they represent. If they don't represent you, well then your SOL, but if they do, and you see something that doesn't add up (LOBBY) or something that needs clarification (rushed policy because of LOBBY) then speak up!!! The law maker in question cannot just make you shut up. You can just make it clear that you want what is fair, and right, and if they try to fight you, go to the media outlets (as gross as they usually are, unfortunate turn of tide in the last 20 years...)
As for doing more good on a bigger scale, well we have a very dry system, and it's not really sexy. I worry about throwing the baby out with the bath water, almost every time I consider what my perfect vision of the upcoming revolution (it will happen regardless of what any of us want). So for now, I just suggest that EVERYONE who is relatively smart, cares about the rest of the community (on a civic level, not just communal) and has any free time at all, just start watching their government tv channel. It may be boring at first, but when you get the hang of what is occurring, it's pretty exciting to see how the rubber hits the road.
Disclosure: I do admit that the city I live in has terrible leadership, and does NOT function the way our county government does. Said city electeds are very self-serving, back room dealing, and largely too stupid to know better than to behave that way. So I'll certainly agree with many who say that governmental entities sometimes are very corrupt. But again, in my experience those are just bad apples, diseasing the otherwise good intentioned structures in place to do work on the people's behalf.
Positive culture change just might be the secret sauce to fix any problem. People are smart!