http://davidharvey.org/ - David Harvey is a Distinguished Professor at the City University of New York (CUNY) and author of various books, articles, and lectures. He has been teaching Karl Marx's Capital for nearly 40 years

Whether you support the ideology it propagates or not, Karl Marx's Das Kapital (http://en.wikipedia.org/wiki/Das_Kapital) is widely considered as a great work. If you wish to learn more on this work, check out : http://davidharvey.org/, where a series of video lectures on this book by David Harvey, who has been teaching this subject for the last 40 years, is being posted.