Blues legend Robert Johnson supposedly sold his soul to the devil to get his guitar skills. Kristy Lee Cook--our Northwest hopeful for American Idol--didn't have to sell anything quite so dear to pay for a ticket to the Philly auditions, but parting with a horse she'd trained can't have been fun. (Unless to rural folk like her--she's from Selma, Oregon--training and selling horses is commonplace. We don't know from farm life.) Kristy failed in her......