Yes, the DVD has a music-only track - with a lot of silence where there's dialogue. I played it with the subtitles on, and here's what's there. It's almost the same as what Jeremiah posted, with the two exceptions noted below (and a different location of the fiddle break). From what I hear, I think Jeremiah's transcription is better than the subtitles. I don't have the CD, but this is what's on the movie. Good song.
-Joe Offer-

When the Mountains Cry
(David Mansfield & Tom Russell)
(On the soundtrack of the Songcatcher)

A lilac comes on a poisoned thorn
It has roots dirty and torn
Young-uns a-playin' as the black crow flies
Mama's weeping; hear the mountains cry.

There was another, a wild dirt flower
Cold was her heart and as dark as dire
Tears on the ground for ("where" seems better, but could be "fer") her love did die
'Neath the bloody moon; hear the mountains cry.

Oh dig his grave narrow and deep,
Set a jug of whiskey by his thirsty feet,
And lay two pennies on his roving eyes;
Two women wailing as the mountains cry.

[fiddle break]

Oh the wind blows weary and the willows sigh
Rivers of sorrow and (but I hear 'when") the mountains cry. (x2)