Kelly Hogan's new album is very good. Here's a song from it . . .
Kelly Hogan - "We Can't Have Nice Things" - YouTube
Rita Wilson, who is more popular for being an actress, just released her debut album which is pretty good. She has some very popular guests on her newest album, which is solid all around imo.
Rita Wilson - Come See About Me - YouTube
I don't know if I'd say he still qualifies as an up-and-comer, but M. Ward has been writing phenomenal songs for years. The new album is excellent.
M. Ward - The First Time I Ran Away - YouTube
If you're more into the Nashville sound, check out Kevin Gordon. He's one of the better songwriters out there, and that says a lot.
Kevin Gordon "Colfax/Step in Time" - YouTube