Grist has compiled an excellent index of articles directed at helping us green folk talk to skeptics. Have a peek:

Gristmill: The environmental news blog | Grist
How to Talk to a Climate Skeptic

Below is a complete listing of the articles in “How to Talk to a Climate Skeptic,” a series by Coby Beck containing responses to the most common skeptical arguments on global warming. There are four separate taxonomies; arguments are divided by:

* Stages of Denial,
* Scientific Topics,
* Types of Argument, and
* Levels of Sophistication.

Individual articles will appear under multiple headings and may even appear in multiple subcategories in the same heading.