The head of the investigation, Detective Senior Sergeant Rhys Johnston, said police had not ruled out foul play but were keeping a "very open mind" and speaking to people in Auckland and the Far North. People had travelled to the tangi, which was for a close relative of Ms Moka's partner, from as far away as Wellington.
"Our number one priority is to locate Barbara. Her family have become increasingly worried," he said.
Anyone who had not yet been contacted by the police was urged to call the Kaikohe station on (09) 405-2960, or Crimestoppers, anonymously, on 0800 555-111.
The last person known to have seen Ms Moka was her 43-year-old partner, who had been with her since she moved to Northland about a year ago. He had been highly co-operative.
Forensic experts have also examined Ms Moka's car, a 1996 Honda Accord station wagon. It had been left at the scene of the crash and was towed away the following day.
The missing woman's mother, Isobel Moka, has made heartfelt pleas on Facebook for her "baby" daughter to get in touch, while her aunt, Aucklander Katherine Siaki, confirmed that no one in the family had heard from her.
"There's absolutely nothing. She just vanished," she said.
She had seemed happy when Ms Siaki's brother had seen her.
"There didn't seem to be any indication that she would go off. It's very strange," she added.
Barbara Ann Moka, who began working at the Copthorne Hotel at Omapere in November, is 1.5 metres tall, of slim build with black shoulder-length hair usually tied up in a pony tail.
She has two tattoos on her neck, one a Japanese symbol, the other an Aquarius star sign.