Toward the end of his life, Omarr wrote a series of astrological guides published by Penguin called "Sydney Omarr's Day-By-Day Astrological Guide". While he authored the books up until his death, his proteges have taken over the work, and Signet continues to publish the series. He believed he had been an astrologer in many previous lifetimes, and he was able to do full planetary horoscopes in his head when given an individual's birth coordinates and birth time. For his Los Angeles Times syndicate columns, he wrote each and every daily horoscope column personally, usually three weeks in advance.