The sentences were handed out at the end of an 18-month investigation by officers from Northumberland Area Command into the supply of class A drugs, particularly in the Morpeth and Ashington areas.
Pivotal to the operation was James Lee Groves, 33, of Chestnut Street, Ashington, who was convicted of conspiracy to supply class A drugs and possesion of a section 1 firearm without a firearms certificate. He was jailed for six years.
Groves was bringing in the drugs from outside Northumberland and then distributing them to others including co-accused Phillip West, 26, of Wellwood Gardens, Morpeth, who in turn would supply street dealers and users. West was sentenced to five years.
As part of this operation Groves used a drugs press to 'cut down' the drugs and then reform the drugs into tablets for onward sale.
Other members of the group were used to conceal cash or drugs in their homes and also launder money.
Police set up an intelligence-led operation and began investigating the lifestyles of the group members, as well as monitoring their comings and goings.
The eight were charged last September.
DI Steve Patrick, Northumberland Area Command, said: "We welcome the sentences for Groves and West, which reflect how seriously the courts view those involved in drug dealing.
Groves was orchestrating the operation, bringing in drugs from other parts of the country and processing it, before supplying it down the chain of dealers.
We will not tolerate the small minority who attempt to bring misery to neighbourhoods by dealing in drugs and committing crime. We would always encourage people to come forward and let us know about problems or concerns they have and we we will take positive action."
Others convicted were:
John Burton, 40, of Rosalind Street, Ashington, convicted of being concerned in the supply of cocaine. Sentenced to 12 months suspended.
Louise Brown, 23, of Rosalind Street, Ashington, convicted of being concerned in the supply of cocaine. Sentenced to 12 months suspended.
John McDonald, 28, of Station Cottages, Morpeth, convicted of money laundering. Sentenced to 12 month community order.
Peter James Farrier, 26, of Choppington Road, Morpeth, convicted of perverting the course of justice. He was sentenced to 12 months suspended and a 150 hour community order.
Henry Pringle, 37, of Second Avenue, Morpeth, convicted of being concerned in the supply of class 'C' drugs. Sentenced to 200 hour community order.
Samantha Pringle, 21, of Fourth Avenue, Morpeth, convicted of possession of Class 'C' drugs. She was given a three year suspended sentence at an earlier hearing.