Rachel Harrington, a country/folk singer from Oregon (who has just completed a long UK tour) does a great version of 'Louis Collins'.

She played it when she came to TwickFolk a month or so ago and I think it's on her "Bootlegger's Daughter" album (you can sample the song at iTunes along with all the others mentioned above)

Incidentally, I first heard and learnt this song off one of Stefan Grossman's 'Kicking Mule' guitar tutorial CDs back in the 70's. His version is the only one I've ever heard that uses an extra chord. Assuming you're in the key of C, over the "six feet" part of the melody he throws in an E7 where most versions maybe just have a C7 or even a plain C chord.

It's just a 'passing' chord but because that's the first version I ever heard that's the way I still hear it in my head...