For purely instrumental blues,you have to have Miles Davis' "Kind of Blue" on Columbia. There are also some re-issue versions as well. William Clarke's "Blowin' Like Hell" on the Alligator label and Roy Gaines "I Got the T-Bone Walker Blues" on Groove Note are also enjoyable. The Muddy Waters mentioned above is excellent. Also,just popped into my head- Sonny Boy Williamson's "Keep it to Ourselves" and the Don Euell Quartet "Yellow Dog Blues" . You could probably order all this stuff from Acoustic Sounds in Kansas at 1-800-716-3553. Enjoy! Nothing's better than good Blues!