So... permissions are in on Greg Brown's song In The Dark With You (which starts Chapter Fourteen) and Stephen Sondheim's Old Friends (which starts Chapter Thirteen). I decided that I'd start Chapter 6 with the public domain Midnight Special rather than Iggy Pop's Sister Midnight, but that was more because it was slightly more appropriate than because of the public domainness or otherwise of the thing. I've also, with a little regret, changed an Alan Moore song-quote into a Ben Franklin Poor Richard quote, because it said the same thing and fitted the theme slightly better on several counts. And because Ben said it first. No word yet on Please Don't Let Me Be Misunderstood, or on the Robert Frost, ee cummings or Yeats quotes. (The Yeats is from The Second Coming, which I almost consider public domain these days, considering it's been quoted to the point of cliche -- which is why the character who quotes it, quotes it when he does -- but I thought it polite to ask.) I'm waiting to see how much Please Don't Let me be Misunderstood comes in at before I start negotiating with the Tom Waits people over a couple of lines of Tango Till you're Sore.
There are probably more than 20 chapters in the book, but all the rest of the chapter headers are from dusty and out of print books.