Many universities post their economics course curriculum online, including lecture notes and a syllabus, so you can learn at your own pace. Start with Introduction to Microeconomics, then move to Introduction to Macroeconomics.
Pick up an economics book (not a textbook) from the library or local bookstore. Good starts are "Discover Your Inner Economist" by Tyler Cowen, "The Invisible Heart" by Russell Roberts and "Economics in One Lesson" by Henry Hazlitt.
Subscribe to the EconTalk podcast (one hour each week) at econtalk.org
The Massachusetts Institute of Technology has more than 40 economics courses online: ocw.mit.edu/OcwWeb/Economics/
Watch economics lectures from top universities for free at Academic Earth: academicearth.org/subjects/economics
The Mises Institute sells a home study course in Austrian Economics: mises.org/store/Mises-Institute-Home-Study-Course-in-Austrian-Economics-P211C0.aspx
If you learn best from reading, buy an economics textbook from Amazon.com (or a local college bookstore) and complete the problem-sets as you read each chapter. An introductory economics text will present the material in the correct order (microeconomics first, then macroeconomics).
If you learn best in a actual classroom environment, see if your local college offers adult education classes in economics. Some colleges and universities also let members of the public audit for-credit economics classes.