'Americans for Justice 4 Harry' is supporting the Northamptonshire family's calls for her to face the British legal system over the crash outside Croughton in August.
"The purpose of this group is to bring attention in the US to this case, to encourage the American government to agree to extradite Mrs Sacoolas if she will not return to England willingly and to let the US government know its own citizens know about this case and desire justice for Harry, as well," the Facebook group description says.
Harry, 19, died in hospital after the crash with a car while riding his motorcycle on the B4031 between RAF Croughton and Croughton on August 27.
Mrs Sacoolas refuses to come back to Britain on her own accord after claiming diplomatic immunity through her husband and flying to the US, despite initially co-operating with police.
The UK Government is working on extraditing her - the American administration has expressed its dismay at the decision to charge her and previously told Harry's family she would never return.
Misty Morris, from Salida, Colorado, set up 'Americans for Justice 4 Harry' as she wanted to turn the 'heartbreak' she felt when hearing about the case into action.
The mother-of-two wrote on the page: "Harry's life mattered and we will continue to fight for justice for him. Thank you for joining us on this fight!"
Harry's family is aware of the Stateside campaign, with spokesman Radd Seiger heavily involved, as Misty wrote they are collaborating on projects.
While Harry's step-brother Ciaran Charles posted in the group: "Thank you for helping us take our campaign in your stride with the goal of spreading awareness across the USA.
"I greatly appreciate your help and support."
A peaceful demonstration calling for the US to support the extradition of Mrs Sacoolas is due to be held outside RAF Croughton, where her husband was based, between 12pm and 5pm tomorrow (Saturday, January 4).