They are from Tuva, and I found out about them via the_ogre via the movie Genghis Blues about the American blues musician/throat singer Paul Pena, and ultimately via Richard Feynman (one of the first Westerners to popularize Tuva).
On this album they are covering a wide variety of mostly Western rock music, from Led Zeppelin to Joy Division. My favorites are the Zeppelin song (see the "listening to" field), "In A Gadda Da Vida," just because—who does "In A Gadda Da Vida" these days? and "Black Magic Woman," which I like a lot more than Santana's version.
I can't remember where I found out about Tuvan throat-singing originally. I have had a CD of Tuvan throat-singing, Deep in the Heart of Tuva, for a long time. It has a Yat-Kha song on it. It also has a couple of Paul Pena songs on it.
I have other overtone-and throat-singing music—from David Hykes' Harmonic Choir and from the Gyuto Monks Tibetan Tantric Choir (a great CD, but not the best choice to take with you to the oral surgeon when having your wisdom teeth out).