Sellers, Hunt, Wallace and three other people were indicted in March on conspiracy charges for their alleged roles in what authorities said was a
violent international cocaine ring that operated in several states, including California and New Jersey.
The charge against Sellers will be dropped if the government believes she has testified truthfully.
Wallace, her former manager, also has pleaded guilty, but it was not immediately clear whether he would testify.
Sellers, dressed in a tight black skirt, a white jacket and high-heeled shoes, appeared calm while testifying.
Sellers - who appeared nude and semi-nude in a Playboy magazine feature that appeared just before her arrest in March - also testified that she had used cocaine since she was 17, sometimes using as much as five grams a day. She said she had not touched drugs since her arrest.
She said that earlier this year she lured a drug dealer named Richard Lump to the apartment she shared with Wallace so Wallace and associates could beat him up for crossing the ring in a deal.
Lump was beaten so badly with a pool cue that he had to be hospitalized. Sellers said she heard the beating by Wallace but did nothing to stop it.
Testifying about the theft of $80,000, she said she had taken it in New York about two years ago and had hidden it in a hotel safe. She did not give details as to how she stole the money.
"I used $10,000 of it and gave the rest to friends," she said.
Sellers faces up to three years in prison and a $500 fine on her guilty plea. However, she could be fined $250,000 as an alternative sentence. She could have faced up to 20 years on the conspiracy charge.
Wallace, who prosecutors said had run a telephone sex company, pleaded guilty to running a continuing criminal enterprise in connection with the cocaine ring and faces a 10-year sentence with no parole. He is in protective custody at an undisclosed location.
