A publishing executive who had just moved into her fashionable Old Town Alexandria town house last Friday was found dead yesterday from a single bullet wound in the brain, Alexandria police reported.

The woman was identified by friends as Connie Mellon, 36, a production and design executive for Time-Life Books Inc., whose offices are four blocks away from Mellon's two-story brick town house at 406 S. Royal St., in the heart of the historic Old Town district.

Police last night refused to confirm Mellon's identification pending the arrival of a relative this morning from New York. Police said there was no sign of a forced break-in at the narrow, 15-foot-wide town house. Mellon's body was found sprawled on a bed in a second-story bedroom of the town house she rented for about $550 a month. Official sources said the death was not a suicide.

Police would say only that the gun used was of a small caliber, but declined comment on whether a weapon has been found.

According to one friend of the woman, someone unknown to family members helped her move into the house Friday. Mellon was then expected to meet a sister in Manhattan the following day for a reunion. She never arrived.

The sister began calling Mellon's residence, but received no answer. Police were called yesterday by Time-Life employes who had become concerned by the absence from work Monday and Tuesday of the punctual and responsible executive.

"She was a bright and witty woman," said one friend in Alexandria, who described Mellon as a quiet-person with prematurely gray hair, who stood about 5-feet-6 inches tall.

"We drove her home from brunch the other day, and she was pooh-poohing our concerns about safety. She said Old Town was safe. After living in Manhattan for 10 years, maybe she became overconvinced that there was no danger here," the friend specuulated.

Mellon moved to Alexandria from New York where she had risen in the ranks of the Random House publishing company. She made the move to Alexandria for professional reasons, a friend said. She had lived at the Old Town Holiday Inn on King Street for about two weeks until she moved into her town house last Friday.

The shooting was the third such incident in the Old Town area in recent months. Last March 12 another Time-Life employe, Mark Chase Sawtelle, was wounded during an afternoon robbery attempt as he walked to his car, parked several blocks away from the Time-Life headquarters building at 277 S. Washington St.

On Aug. 28 Alexandria optician Carol Ann Dodd was shot once in the back and killed during a 2 p.m. robbery attempt of her shop at 215 N. Washington St. One man was convicted in the Sawtelle case, and two people was indicted this week by a grand jury in the Dodd case.

After Mellon had arrived in Alexandria, she contacted people she knew about a place to live. "She didn't want to live in a high-rise and have to go through the singles scene," said one friend who had discussed the various options with her. "She wanted a little garden and a fireplace. We encouraged her to get a town house," the friend said.

Another source recalled, "Connie doesn't drive. She wanted to be close to work."

Accordiing to friends, Mellon was a native of South Carolina who had attended the University of Kentucky. Her work at Time-Life involved all aspects of physically producing a book, from choosing the proper grade of paper and cloth for the binding to selecting a cover design. Mellon had recently returned from a business trip to Indiana, and was buoyed by the experience. "She just loved it," a friend said. "They really took her in at Time-Life, and made her feel at home."

Police last night were knocking on doors of the town houses in the area, searching for information about the few hours Mellon spent in her new home. Inside the small town house, which Mellon once described to a friend as "teeny," were cardboard cartons filled with books and personal belongings. A lamp stood on the floor, and a bag of old newspapers was piled outside.

A friend said last night that relatives were flying to the side of Mellon's aged father in South Carolina. He has a heart condition and had not yet been informed of his daughter's death.

Police scheduled an autopsy for Thursday.