When a musician dies, it is rarely the end of their story. While death can propel megastars to even further success, artists overlooked in their lifetime might also find a new type of fame. But a badly timed move or the wrong deal can see the artist die all over again. Colonel Tom Parker, the former carnival huckster, understood this high-wire act implicitly and the posthumous career of Elvis Presley has provided a template for everyone else. Estates...