Nambucca Heads detectives arrested the 33-year-old at Valla at 12.40pm yesterday.
They took her to Macksville Police Station, where she allegedly refused to be interviewed by police, and was subsequently charged.
Detective Senior Constable Dave Stuart alleged police were given information earlier this month that the woman had sought the murder of another Urunga woman, 40.
Investigators then launched an operation where the 33-year-old was introduced to an undercover police officer, he said.
The woman remained in custody overnight ahead of her appearance in Coffs Harbour Local Court this morning.