Perhaps "Little known" can be defined as whether allmusic.com has any (or more than one line) on the person. Many mentioned above were well-known locally - some as local "favorite sons" for decades. But never left home. Most started that way, I guess. I could easily name a dozen good singers/singer-songwriters well-known on the Florida circuit but unknown outside Florida. Or even outside Orlando.

Mike Miller: I'm pleased you mention Joe Aaronson at last - you didn't earlier. He had a huge effect on "spreading the gospel" in the 60's. I'm glad he continued. You don't mention me, though. That's ok. I wasn't even known downtown - just on campus!

Peace: (et al)
"His rendition of 'Green Green Rocky Road' is the absolute best I ever heard." You mean Chandler? Still alive, I believe. Born 1935. One of the few good things I have to say about _Rise Up Singing_ is that they give proper credit to this song. To Chandler, yes, but he was fairly well-known. Thing is, also to beat poet Bob Kaufman. They actually collected it together from street kids in New Orleans. Len sang it and taught it directly to Van Ronk. That created the East coast bluesy veresion. Chandler went west and taught it to a fine little-known San Francisco singer named Tom something. That created the softer West coast version.

Speaking of San Francisco favorite singers. I've been trying since '59 (you know, the 60's had to get started somewhere - it was in the 50's. Many of them learned from 40's singers. And so on...)
to track down the favorite San Francisco singer. He was actually in the Union and wouldn't take less than scale. The local Guthrie - or Suffet. Any help appreciated.