Lipsey & Chrystal: Economics 12e
AmosWeb Encyclonomic Web·pedia (just trips off the tongue!) is a useful resource, but does eventually require you to register. It offers competent definitions of positive and normative statements in economics (search for "positive economics" or "normative economics").
EcEdWeb's page on Economic Data and Information (at the University of Nebraska at Omaha) has links to a wealth of sites offering economic data. There is inevitably a US-centric bias, but they do list non-US sources too.