Classic Chicago Blues:
Muddy Waters (originally from the Mississippi Delta)
Howlin' Wolf (originally from the Mississippi Delta)
Next Generation Chicago Blues
Junior Wells (Wells also plays a mean Harmonica)
Buddy Guy (Also a guitar hero)
Bobby "Blue" Bland
Blues Featuring Harmonica
Rice Miller "Sonny Boy Wiliamson" (Made his name in Memphis, but originally from the Delta)
Paul Butterfield Blues Band (also from Chicago)
Charlie Musselwhite (also from Chicago)
Little Walter (also from Chicago)
James Cotton (also from Chicago
Modern Harmonica Based Blues
Blues Traveler
J Geils Band
Classic guitar hero type blues:
Albert King
BB King
Modern Guitar Hero based blues:
Mike Bloomfield
Early Allman Brothers with Duane Allman
Eric Clapton
Jimmy Hendrix
Jeff Beck (Truth Album)
Led Zeppelin (I and II)
Cream
Stevie Ray Vaughan
Johnny Winter
Robert Cray
John Mayall's Bluesbreakers (early Brittish blues band that featured Eric Clapton among many others)
Link to Bluesbreakers info --
http://en.wikipedia.org/wiki/John_Mayall_&_the_Bluesbreakers
Classic Delta Blues
Charley Patton
Robert Johnson
Skip James
Son House
Blind Lemon Jefferson
Big Bill Broonzy
John Lee Hooker
Elmore James
Mississippi Fred McDowell
Sonny Terry & Brownie McGee
Next Generations Delta Style
Taj Mahal
Keb' Mo