That's awesome. This is what democracy looks like.
I got hooked attending some townhalls on my pet topic. I've learned so much about politics, policy, etc. these last 8 years.
#1 Show up.
#2 Keep showing up.
#3 Bring your friends.
It's ridiculous how few people shape policy. The upside is adding a few more people to the debate can significantly shape outcomes.
If you become credible (learn a topic well enough to speak to all points), and you pack council chambers with your supporters, you will change policy.
Everyone focuses on campaigns. The real action is in policy. Politics is a dirty, filthy business, but it's still worthwhile.
I strongly recommend Camp Wellstone. There's an "activist" track. Anyone aware of methodology or project management will grok their techniques immediately. The focus is policy vs products.