I've come into what is obviously a carry over from another thread, so I hope I'm not repeating anything which has been said already. However, as is well known, the American south has been extensively trawled for prison worksongs. Anyone interested in prison songs should definitely investigate the following:

Deep River of Song. Big Brazos: Texas Prison Recordings, 1933 and 1934. Rounder. 11661-1826-2
Prison Songs: Historical Recordings from Parchman Farm 1947-48: Vol 1: Murderous Home. Rounder 1714
Prison Songs: Historical Recordings from Parchman Farm 1947-48: Vol 2: Dontcha Hear Por Mother Calling? Rounder 1715
Prison Worksongs Recorded at the Louisiana State Penitentiary at Angola, L.A. Arhoolie 448
Angola Prisoners' Blues Arhoolie 419
Angola Prison Spirituals Folk Lyric 9036
Wake Up Dead Man: Black Convict Worksongs from Texas Prisons Rounder 2013

The first three are from collections made by John and/or Alan Lomax and contain some electrifying stuff.

The Angola CDs were collected by Harry Oster in the late 1950s. Check the Arhoolie/Folklyric catalogue for recordings of individual singers made by Oster in the Angola pen.

Also worth investigating are the Rounder CD reissues of the field recordings originally published by the Library of Congress. I can't recall any which were exclusively devoted to prison songs, but there's a mountain of wonderful material on them.

Finally, there's also an album of toasts (monologues, mostly obscene) called Get Your Ass in the Water and Swim Like Me: Narrative Poetry from Black Oral Tradition. Rounder 2014. Like Wake Up Dead Man, it was collected in Texas penitentiaries by Bruce Jackson.

Whilst on the subject, BBC2 televison is showing a documentary on Sunday 13th at 22-00 hrs. It's called Prisoners of Katrina and tells the story of what happened when Hurricane Katrina hit the New Orleans city prison. It's primarily concerned with the events of last August but does, I gather, go into the southern penal system in some depth.