If we're talking late 60's, I suggest a few:
Jethro Tull - my all time favorite prog. rock band. Their style ranges anywhere from hard rock to blues to folk to...
Captain Beefheart & His Magic Band - suggest "Safe As Milk" to start out with as they can be an acquired taste. They're a unique mix of blues/jazz/rock/experimental all mixed into one.
Taj Mahal - Blues all the way.
Jethro Tull - my all time favorite prog. rock band. Their style ranges anywhere from hard rock to blues to folk to...
Captain Beefheart & His Magic Band - suggest "Safe As Milk" to start out with as they can be an acquired taste. They're a unique mix of blues/jazz/rock/experimental all mixed into one.
Taj Mahal - Blues all the way.