Damn, I'd like to get on Pandora! I love that website; the best radio-ish idea to come along since... well, radio itself. I have a Portishead station, a Blue Grass station, Jethro Tull station, a Wilco station, a King Crimson Station, an Elliot Smith station, an Electronica station.... oh so many stations. I've submitted my music like a good boy. But I think they respond more to fan requests than to artists themselves. (Either that, or they just don't think much of El Shiperino.)
Here is the link. I hope my good friends go to it, then click "help" to see how to suggest an artist: