You want blues?
I got yer blues right HERE, baby!
Sounds like you've found the 50's-60's electric blues,
but you're just scratching the veneer.
If you like the Muddy Waters & Paul Betterfield sound, look into
what is termed 'Chicago Blues'. Muddy Waters, John Lee Hooker,
Magic Slim & the Teardrops, Buddy Guy, Albert King (better than his brother, B.B., IMHO), Otis Rush, Otis Spann, etc. Check out a lot of the 50's-60's artists on the old Chess record label. BTW, most of the Chess songs, played by Muddy, Howlin', etc., were actually written or arranged by Willie Dixon.
Newer good stuff of the electric nature include Coco Montoya, Luther Allison, (Bernard Allison (son of Luther Allison), Sonny Landreth (Clapton called Landreth his favorite contemporary blues guitarist), Eric Sardinas (electric dobro - very Johnny Winter-like), Anson Funderburgh......I could go on all day.
PM me your address & I'll throw together a tasty Blues sampler for you.
Probably take me a few weeks, though, as I've got my hands full with some CD projects & a couple of guerilla vacations (hit n' run).