Compact discs have created new markets for classic blues--and vice versa. Below five reissues sure to please purists and neophytes alike. Charley Patton: Founder of the Delta Blues, 1929-1934(Yazoo).

It was Robert Johnson’s boxed set in 1990 that proved that blues recordings more than 60 years old could sell more than a half-million copies and go platinum — especially when his best-known songs ...