work books
There are many books available; some are listed below.

However, the Work cannot exist in isolation and for those seeking, it is necessary to find a group of people working directly with the ideas and methods expressed by Mr. Gurdjieff. A good exposition of the ideas is contained in Ouspensky's "In Search of the Miraculous".

In Search of the Miraculous - Fragments of an Unknown Teaching
by P. D. Ouspensky

Ouspensky spent nine years with Gurdjieff, during which he recorded Gurdjieff's teachings as presented to his pupils.  It is probably the most concise record and explanation of Gurdjieff's philosophy, psychology and cosmology.
ISBN 1-85063-090-09

all and everything - beelzebub's tales

Beelzebub's Tales to his Grandson - An Objectively Impartial Criticism of the Life of Man (All and Everything - First Series)     by G. I. Gurdjieff

An allegorical tale for the study of his teachings. Gurdjieff's aim, as stated at the beginning of the book, was "To destroy, mercilessly, without any compromises whatsoever, in the mentation and feelings of the reader, the beliefs and views, by centuries rooted in him, about everything existing in the world."
ISBN 0-7100-7875-7

Meetings with Remarkable Men
(All and Everything - Second Series)
by G. I. Gurdjieff

Autobiographical recollections of various "remarkable men" that Gurdjieff met during his life, written with the aim:  "To acquaint the reader with the material required for a new creation and to prove the soundness and good quality of it."
ISBN 0-330-25569-X

Teachings of Gurdjieff - A Pupil's Journey
by C. S. Nott

C. S. Nott, an associate of A. R. Orage and P. D. Ouspensky, first met Gurdjieff in New York. This is the first of two books about his life and experiences with Gurdjieff and the teaching he received.
ISBN 0-7100-8937-6

Idiots in Paris
by John G. Bennett & Elizabeth Bennett

Diary entries from John and Elizabeth Bennett covering the few months before Gurdjieff's death in Paris on 29 October 1949.
ISBN 0-900306-47-5

Diary of Madame Egout Pour Sweet by Rina Hands

After spending a year with Gurdjieff in Paris, Rina Hands returned to England and worked with J. G. Bennett to establish the Yorkshire Gurdjieff Group based in Bradford. Her leadership of this Group, the Bradford Gurdjieff Society, continued until her death in 1994.

In Diary of Madame Egout Pour Sweet she describes the readings and meals in Mr Gurdjieff's Paris flat, and gives some insights into the Science of the Idiots.  She gives a first hand view of the way Gurdjieff taught in his last year.
ISBN 0-89756-017-5

The Reality of Being - The Fourth Way of Gurdjieff
by Jeanne de Salzmann

As his closest pupil, Jeanne de Salzmann was charged by Gurdjieff with carrying on his teachings of spiritual transformation. Twenty years after her death in 1990, the notebooks that Madame de Salzmann filled with her insights over a forty-year period were translated and published for the first time. This book provides a complete and uniquely authoritative guide to Gurdjieff's ideas and to his methods for liberating ourselves from the state of waking sleep in which we live our lives.
ISBN 978-1-59030-815-8