Miller, 19, is described as a white woman, 5 feet 4 inches tall, 125 pounds, with brown hair and blue eyes.
Police described the body found Monday as white and in her late teens or early 20s, between 5 feet 2 and 5 feet 5 inches tall. She had medium to light brown hair, a gap between her front teeth and was wearing an extra-large, black, Fruit of the Loom short-sleeve shirt with a "New Orleans Bourbon Street" logo.
She also was wearing a dark green bra, short blue jeans and black shoes.
Miller is wanted on two counts of accessory after the fact, felony theft, auto theft and unauthorized use of a motor vehicle.
Crime Solvers has offered a $1,000 reward for information on her whereabouts.
Miller reportedly was last seen on Nov. 20 in the parking lot of Big Lots on Maryland Avenue.
She is believed to have been with a man accused in the fatal beating of Darrius Allen Fetterhoff of Greencastle, Pa.
Fetterhoff, 58, of Grant Street, was struck in the head, rolled over a 90-foot embankment, and left for dead on Aug. 20, according to police.
Fetterhoff was found along the bank of the Conococheague Creek east of the Creek Bridge on Broadfording Road on Aug. 25.
He died on Aug. 28. Authorities said he had suffered multiple head trauma and complications.
Fetterhoff's wife reported her husband missing Aug. 20 to the Greencastle Police Department. Earlier in the day, according to investigators, Fetterhoff had dropped his wife off at work and driven to Hagerstown.
According to statements given to police by Miller, Fetterhoff picked her up that morning and they had sex. Afterward, she picked up James Thomas, 30, of 441/2 E. Franklin St. in Hagerstown, who was arrested in connection with the beating.
Investigators later learned that Thomas' real name is Thomas Clifford Wallace.
Wallace told investigators that he sold Fetterhoff $40 worth of crack, court records said.
According to statements to police by Miller, Wallace told her to drive to the Broadfording Road area after Fetterhoff refused to offer more cash for drugs. Along Hopps Landing, the man forced Fetterhoff out of the car and struck him in the head with a rock, according to allegations contained in court documents.
Miller told authorities that Fetterhoff fell down a 90-foot embankment, according to court papers.
A Washington County grand returned a murder indictment against Wallace in October.
The murder charges against Wallace later were dropped because Miller could not be found to testify.
In February, Wallace was sentenced to 11 years in prison on the drug charges.