If you want an easy-to-find, newer release, try Alison Krause and Union Station's new double live CD. Don't be scared off by the fact that it's a live performance--it is a superb recording. If you haven't heard Alison Krause, it would be a good introduction to one of the best female vocalists anywhere. She also has a great band, especially Jerry Douglas on dobro.
Of course, you can't go wrong with Joni Mitchell's "Blue."