One approach is to go to the MIT OpenCourseWare website, look for the economics department, and look at their reading lists. Of course, that's going to be mostly academic reading (textbooks, etc.). But if you want to learn the basics, it's probably safer to start there than the pop econ books (and I would dispense with most heterodox reading before you're able to assess them within a larger framework). Two good books that haven't been mentioned here: Economic Theory in Retrospect, by Mark Blaug. Very useful to get a good historical grounding in the main ideas that compose today's orthodox economics. The Applied Theory of Pirce, by McCloskey. Your usual microeconomics textbook, but far more thorough, insisting a lot on grasping the intuition behind the concepts. Available for free from the author's website here: http://www.deirdremccloskey.com/docs/price.pdf
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