The book of Bokonon is found in the Elona+ mod of Elona. It is obtained by completing the mages' guild part of the Guild Quest Level 40.
Using the book will display the text, "According to please the live foma". After this, a Wrang-wrang will join you. If your party is full when you read it, the book will still be consumed.
It is presumably referencing this, which is from a book called Cat's Cradle by Kurt Vonnegut.
Customization[]
The item sprite ID for the book is 429 (Row 13, Column 0) using the item sprite zero-based position system. It has no tint, and so looks like an ancient book.