Keb Mo has quite a few acoustic songs on his albums.
Depending on how much you like early blues, and how "authentic" you want to get, there are a number of early, great acoustic blues men that you should listen to, including: Robert Johnson, Huddie Leadbetter, Big Bill Broonzy (one of my all-time favorites), Blind Lemon Jefferson, Mississippi John Hurt, Son House, Howlin' Wolf, Willie Dixon (one of the most important influences on Mick Jagger, The Beatles, and other English "blues" groups of the 1960's), Sonny Terry and Brownie McGhee (Piedmont-style blues), Reverend Gary Davis, etc.
If you want to really delve into the blues, then you can get a lot of great information from the book by Bill Wyman titled "Bill Wyman's Blues Odyssey", which can be ordered from Amazon.com. Wyman is a former Rolling Stones member, and his book offers a very good introduction to the styles of blues and the great singers of each style (from Delta blues through modern urban blues).
"Screamin' And Hollerin' the Blues" by Charley Patton. Contains all known recordings by Patton plus assorted recordings by Son House, Howlin' Wolf and Willie Brown. The recordings date from the early 30s so don't expect high fidelity, butt the music is amazing.
Charley Patton *is* the beginning. The recorded Delta Blues tradition
starts there. The recordings were originally done on cheap plastic like
all "race" records and these recordings were recovered when producers
went door to door in the Delta and found local residents who still had
Patton's records long after his death. So, the recording quality is
sketchy, but the depth of Patton's emotions and the beauty of his
amazing play shines through with crystal clarity. Patton taught Robert Johnson, Howlin' Wolfe, Muddy Waters, and many more. Any serious blues enthusiast should start with Charley Patton, Robert Johnson,
Son House, Muddy Waters, Howlin' Wolfe -- that's where it came from
and there's nothing more authentic than that.
Some great suggestions so far, particularly anything that Willie Dixon played on, and any recording you can find of Son House. However, to make a less traditional suggestion, a good acoustic recording, with some blues aspects, is Eric Clapton Unplugged. I find this to be an especially involving recording, and I often use it when auditioning new equipment.
With regard to the other suggestions, I have many recordings by the above-referenced artists, but so many of them are not well recorded, mixed, or produced. Any suggestions on specific recordings that are worth acquiring? I was fairly impressed with what I heard on the PBS airing of Martin Scorcese's "The Blues", so I have high hopes for the derivative CDs and DVDs of that production.
I second the vote for Eric Bibb. All three albums on hybrid SACD/CD on the Opus3 label are great and each of his several others on regular CD (that I have listened to) are good as well. Great music which is fabulously recorded to boot. Start with the Opus3 discs - I recommend " Just Like Love" as a starting place.
Mississippi John Hurt - Today
Son House - Death Letter
Joseph Spence - Music of the Bahamas (phenomenal guitar playing!)
Reverend Gary Davis - Ragtime, Sun is Going Down, Pure Religion, Guitar and Banjo
Robert Johnson - King of the Delta Blues
John Hammond - Country Blues
Cephas and Wiggins - Dog Days of August
Rory BLock - Rhinestones & Steel Strings
Eric Bibb - Spirit
R.L. Burnside - Acoustic Stories
Kelly Joe Phelps - Shine Eyed Mister Zen
Guy Davis - You don't know my Mind
And 3 that few have heard of:
Jackson Delta - Lookin' Back (this is a superb album)
Bill Bourne - No Special Rider
Jimmie Lee Robinson - ... all my life
Lots of good suggestions so far that I don't have to mention, and I didn't read all of the lists, but......
- Otis Taylor on Northern Blues or Telarc labels.
- any Harry Manx on Northern Blues, and also with Kevin Breit in "Jubilee"
- Somebody already mentioned Guy Davis on Red House Records, but on the same label: Paul Geremia, Koerner Ray & Glover.
- Chris Smither and John Hammond.
- "Memphis BBQ Sessions" with Kim Wilson and Big Jack Johnson, on MC Records. It was nominated for a Handy Award.
I've got a million of them...