• FactCheck.org (Annenberg sorts political truths from half-truths). See, for example, A Campaign Full of Mediscare, 8-22-12. (Obama and Romney both aim to slow Medicare spending. But each accuses the other of hurting seniors in the process. What are the facts?)
• Fairness & Accuracy In Reporting (FAIR) (Challenging media bias and censorship since 1986). See for example Paul Ryan's 'Self-Reliance'
• The Fact Checker (Glenn Kessler, Washington Post column, The Truth Behind the Rhetoric).
• PolitiFact.com (nonpartisan political fact checker, whose truth-o-meter ranks findings from "true" to "pants on fire"), St. Petersburg Times service, and here are articles on current issues, eventsOnThe Issues (every political leader on every issue)
• Real Clear Politics
• The Reddit Edit . (Here's A journalist's quick guide to Reddit (Jeff Sonderman, Poynter, 8-30-12)
• Miscellaneous research tools (SPJ, Journalists' Toolbox)
For checking email stories or warnings you suspect are unreliable:
• Snopes.com (E-mail story sound too good or scary to be true? Check to see if it's an urban legend)
• Truth or Fiction (another reality check on email hoaxes, rumors, viruses, and advisories). See if that Kenyan birth certificate for Barack Obama is real or faked.