Recently watch this British documentary called "The Global Warming Swindle."
I think it is an excellent documentary, and is a great counter-punch to Al Gore and his environmentalist minions. Two things in the video that stood out to me as all-important to the environmental change "discussion." First was the interview with the co-founder of GreenPeace and one of the reasons why he left the movement.
The second was the "inconvenient fact" that Al Gore left out of his documentary "An Inconvenient Truth." This is the fact that global CO2 levels FOLLOW, rather than CAUSE, environmental temperature change. In the section describing the research of ice core samples, this is brought out rather dramatically.
Watch the video, and judge for yourself. You at least need to see both sides of the argument.