Gargoyle has the answer right, and there's only one right academic answer to the explicit question. If you know who wrote it, it probably hasn't passed into oral tradition yet, and likely hasn't wandered through variants in 8 languages by people who nver heard the radio. Such songs can't be common in English any more.
My preferred variant on the implicit question is 'the best writer of songs that SOUND like folk songs,' and I have never heard anyone better at that than Stan Rogers. Gillian Welch is the best still living and writing in English that I'm familiar with.