J.M. Porter, ed., Luther: Selected Political Writings.
Porter excerpts important political selections from Luther. The important political works are, of course, available separately, and include: Temporal Authority, To What Extent Should it be Obeyed?; To the Christian Nobility of the German Nation; and The Freedom of a Christian. (Some of these works are also available at http://www.iclnet.org/pub/resources/text/wittenberg/wittenberg-luther.html).