Ernst's first sessions book was available through collectors channels at the time. Not particularly Elvis collectors channels but Record Collecting channels. I bought them, when they came out, when I found them.
I really don't remember exactly when was the earliest, and although I THINK I have TWO editions (slim softcover) plus the US Popular Culture Ink hardcover (which was a different company name first, Pierian Press, which is probably the one I have), they are buried in boxes I have not unsealed since I moved in 1987.
The Pierian Press edition, circa 1985, is still listed on Amazon as a used item at an incredible price ($77.00+). That company also had an early website, but I can't find it in Google now.
I wonder what the original softcover versions are worth?
"A Life In Music" draws HEAVILY on Ernst's earlier books.
[I also see that Amazon, at this moment, has Day By Day for "Bargain Price" $12.99, which someone mentioned seeing in a Books-A-Million store on some other message a few days ago]
Ernst's first book, at least the earliest one I have, was published well before Elvis died and did not include the 76 recordings. It did include photos of the 1957 two-track tape box. (This is from my memory.) And the constant misunderstanding about the word "binaural" as used for those TWO-TRACK recordings began there (which has irritated me for some TWENTY EIGHT YEARS now).
When Lichter's book came out anyone who had Ernst's book could see the sessionography was a complete steal from Ernst. But also, it was basic info which RCA obviously would provide. But Lichter clearly copied Ernst.
Not to reduce the impact of Ernst's EARLY work, but RCA did indeed have the basic MASTER information intact--master number/title/date--that's THEIR BUSINESS--which is what Ernst printed, with his analysis and interesting investigations and GUESSES.
I damn near memorized Ernst's book - BEFORE Elvis died.
Discographies of that type, more or less, were very common at the time for many "cult" type artists. I have a few others for other artists. All pretty much self-published by the respective fanatics of the particular artist. Ernst was the first to do it for Elvis, and everyone following has copied him.