I listen to Lore and Conan Needs a Friend (which have been mentioned), so I'll throw out another one I love: Cocaine and Rhinestones. It's put on by David Allan Coe's son, and he focuses on stories surrounding country music in the 1900s. Some of the topics include Okie from Muskogee, Harper Valley PTA, The Pill, Spade Cooley killing his wife, and a bunch of others.