http://ocw.mit.edu/courses/sloan-school-of-management/15-810-introduction-to-marketing-spring-2005/
University of California, Irvine OpenCourseWare
Kutztown University – Small Business Development Center (kutztownsbdc.org)
http://www.kutztownsbdc.org/eLearningCourses/sba-analysis.asp
U.S. Small Business Administration (sba.gov)
http://www.sba.gov/content/sba-delivering-success-marketing-101
About Marketing (about.com)
http://marketing.about.com/od/brandstrategy/tp/brandstrategydev.htm
Wikiversity Business School (wikiversity.org)
http://en.wikiversity.org/wiki/Principles_of_Marketing
McGraw-Hill Higher Education (free-ed.net)
http://www.free-ed.net/free-ed/BusFin/Marketing/marketing01_TOC.asp
Last but not least, you can visit above sites to get information about free marketing courses online.