Norman Blake's "Billy Gray" (which is in Digitrad under "True Love Knows No Season" or something to that effect) involves murder, although I don't know if it fits the pattern Kim wants. (It was also recorded by Robert Earl Keen, who probably has a number of murder ballads of his own, if Kim wants discographic information, too.)

"Girl Behind the Bar" is a classic (I've got it on the Red Clay Ramblers & Fiddlin' Al McCandless and on Jay Ungar's Catskill Mountain Goose Chase LP).

I assume "Omie Wise" and "Pearl Bryan" have already been mentioned.