I am sure Gene will be responding here, as he is the most enthusiatic of the bunch when it comes to slide. One of the founding fathers is Blind Willie Johnson. Also check out Tampa Red, Blind Willie McTell, Blind Boy Fuller, Robert Wilkins, and Fred McDowell. Some modern players include Ry Cooder, Taj Mahal, John Hammond, Roy Rogers, Sam Mitchell, and John Mooney. Stefan Grossman's Guitar Workshop (973-729-5544) has a catalog full of lessons and vintage footage (including bottleneck).