Living a Green life

After watching the website the story of stuff( previous post), I of course think about my own life and trying to make sure i live as green as possible. How does one change to reflect this? I buy more local if i can, I buy secondhand if possible, and i try to decide what i really need versus a short term want. But what else is there to do? My job keeps me on the road a lot so going without a car is not a reality... i already try and put as many errands on one trip to town as possible, and limit how often i go to town anyway.
I am going to research some ideas and post them as i find them...i welcome your suggestions also :)