NewScientist.com has done a great job in compiling a list of the 26 great misconceptions about Global Warming and climate change. This is an amazingly complex subject and the naysayers have endless arguments disclaiming the facts about how our world is changing for the worst. Now with the resources at NewScientist you can find a link to a specific article that in turn link to original research that will help you understand the details and refute arguments against Global Warming.
For those who are not sure what to believe, here is the NewScientist round-up of the 26 most common climate myths and misconceptions.
There is also a guide to assessing the evidence. In the articles they've included lots of links to primary research and major reports for those who want to follow through to the original sources.