I heard the Politifact site mentioned on NPR news today. It has a "truth-o-meter" to evaluate statements made by political candidates and their supporters. It doesn't appear to be partisan, and I've found it useful. Because you know politicians say things that might be technically true, but you know they're not telling the whole story. This site lists the statement, its rating, and if you click through to read more details, you'll get the whole story.