The three stigmata of Palmer Eldritch
By: Philip K. Dick
Series: Macfadden books -- 60-240
Publisher: Macfadden-Bartell
Published: 1966
Place of publication: New York
Language: eng
Number of pages: 191
First sentence: His head unnaturally aching, Barney Mayerson woke to find himself in an unfamiliar bedroom in an unfamiliar conapt building.
Description: Originally published by Doubleday in hardcover in 1965. Copyright date 1964

From the back cover:

IT WAS ALWAYS SATURDAY

You woke each morning with the comfortable feeling that you didn't have to go to your job.  Instead, you could climb into your brand new Jaguar, pick up your girl and go to the beach.

Except that when you looked into your shaving mirror you saw a note tacked up, written in your own hand:

THIS IS AN ILLUSION.  MAKE GOOD USE OF YOUR TIME, BUDDY BOY.

Because the illusion wouldn't last.  And soon you would be back as an unwilling colonist on the dreary planet Mars.
Notes: King copy given by Dr. Richard D. Erlich, Miami University (Oxford, Ohio)