From the skimpy "liner notes" it seems these tracks were recorded in Los Angeles in December, 1971, and not intended for release. All thirteen titles are Waits' compositions as well. Other than that, and not possessing a complete Waits catalog, I can't tell which of these are unavailable in any other form, and which, if any, were later rerecorded.
All tracks produced by Robert Duffey. My guess is that these are early demo tapes... not from the sound quality (which is excellent throughout), but from the performances. Unlike Waits middle-period recordings, in which he played a highly stylized bum/loungelizard/minstrel, and unlike his more recent work that's stretched much farther out, these recording sound much more raw.
A few of the tracks have Waits' late-night jazz sound, but it's less contained, less scripted for a particular image than it became later. The guitar-bass-drum trio of "Goin' Down Slow" gives way to a slide guitar that seems to alternate between C/W and Blues licks. There's an uncharacteristic electric piano mixed in as well. "I'm Your Late Night Evening Prostitute" is one of Waits' characteristic first-person broken-down cabaret lounge-lizard pieces, sung to a piano accompaniment. (You can almost hear people dropping dollars into the tip jar).
Even more of the tracks have a very spare folk sound. "Poncho's Lament" features Waits' plaintive vocal accompanied only by an acoustic guitar. At moments reminiscent of Woody Guthrie (or perhaps the Dylan or Springsteen variations thereof). "Had Me a Girl" has a country-blues sound to it, with Waits' riffing on the line "...my doctor says I'll be alright, but I'm feeling blue..."; the rest of the lyrics are fairly insipid rhymes, but the melody and singing are irresistible.
Overall I really like this disc a lot. There's a closeness between singer and listener that often seemed, for me, to be missing from some of Waits' later recordings. The variety of musical approaches is similar to his more recent recordings, but the styles are less extreme: some roots-folk, some quiet electric blues, some loungy jazz. This disc seems more the work of a struggling singer-songwriter than an artist crafting a record.