I really like Howlin' Wolf (which is the band Hubert Sumlin got started with, isn't it?).  I downloaded a bunch of his (and many other of the more "original" Blues musicians who were recorded in the days before the "British Invasion" and Rock "happened" - Scrapper Blackwell - great guitarist, Muddy Waters, Son House, etc.) music and Albums from Emusic.com, and some people don't think a lot of him, but I like him and his BIG voice.  You won't go wrong with Albert King or Otis Rush either, IMO!

Jim