when did the prologue first appear in William Burroughs 'Junkie'?

Answer 1

At first, it was called a preface:

"Burroughs’s preface (now restyled as a ‘prologue’) still stands first in the current edition, but relegated to the rear of the text is the glossary of junk lingo and jive talk with which he sought to initiate his square readership to the hip world. And for Burroughs the term ‘hip’ referred resolutely to the heroin subculture. The bracketed editorial notes have been excised."

If you'll go to the second link (google books, which can't be cut and pasted), you'll find the history of the "preface/prologue.