Gas:http://tonto.eia.doe.gov/oog/info/gdu/gasdiesel.asp 

Dollar: http://useconomy.about.com/b/2008/03/03/the-value-of-the-dollar-and-how-it-affects-you.htm

Food price:http://www.latimes.com/business/la-fi-food20-2008may20,0,1939435.story?track=rss