They say Kim Richey is country, but she's also got a solid following on adult alternative radio, which is where I first heard her. (She also did several of the songs for the soundtrack of the TV series "Nashville," including "Why Can't I Say Goodnight" as performed by the characters Scarlett O'Connor and Gunnar Scott.)
Her songs have also been recorded by Trisha Yearwood ("Believe Me Baby (I Lied)"), Radney Foster ("Nobody Wins"), and Brooks & Dunn ("Every River").
If you're a fan of "Angel," the spinoff series of "Buffy the Vampire Slayer," you probably remember her song "A Place Called Home," which was the soundtrack after Fred's death in the final season.