Nearly 300 people have now shared their stories or searched for birth parents and siblings through website I'm Adopted.
Founder Alex Gilbert, who grew up in Whangarei after being adopted from Arkhangelsk, Russia, has also begun sharing videos of adoptees telling their stories through the I'm Adopted Facebook page.
"We're hopefully going to video more people and we want to have more meet-ups.
"We also want to try to tee up more support groups."
He said the website offered a resource guide to assist people in finding birth families, as well as a forum for people to share stories, advice and information.
"I get a lot of messages and people asking me for advice."
Mr Gilbert started the project two years ago after being reunited with his own birth parents.
He ran the I'm Adopted website and Facebook page on his own, although he had help from two "ambassadors" for special projects and meet-ups.
The organisation was registered as a charitable trust this year.
Mr Gilbert worked full-time as well as running the organisation and administering the website.
He started I'm Adopted in 2015 to help people trying to find their birth families as well as allow them to share stories to help others.
The Facebook page has more than 21,000 likes and at least eight Russian media organisations have shared the story of I'm Adopted.
Three people have so far had their video stories uploaded to the Facebook page - Alex Gilbert, Romanian adoptee Alex Kuch and Aleisha Snell.
Ms Snell shared her story of finding her birth family on video through the organisation's Facebook page.
"I know there are a lot of people out there who go through a similar process," she said.
"I was wanting to provide hope for others, to show them that it can happen."
Ms Snell, who works in hospitality, found members of her birth family after meeting a Russian woman at her workplace by chance.
"We got chatting and two weeks later she managed to find my family."
She was then reunited with her aunt and sister in Russia through a TV programme.
"It was very overwhelming, it was very surreal . . . It didn't hit me until after I landed in Russia that they may not be the people I thought they were."
The meeting went well, though, and she began talking to her sister and aunt every day.
Her birth mother has died and she had little information about her birth father.
Ms Snell planned to return to Russia in just a few weeks to visit her relatives.
Mr Gilbert remained in touch with his birth parents after their meetings, particularly his birth father.
He has visited them in Russia twice, in 2013 and 2015, and both birth parents have met his adoptive parents.
He set up the organisation to help others in the same situation.
Mr Gilbert was unsure how many people had successfully traced their birth parents, but one American woman who posted on the site found her Russian birth parents within a week.
More than 600 children were adopted from Russia and brought to New Zealand in the 1990s, he said.
"I know that there are a lot of adopted kids from Russia and Romania in Whangarei."
I'm Adopted is open to people from any country, although it has been particularly popular with those who were adopted from Russia.
The site - as well as its Facebook pages in English, Russian and Spanish - has been popular with people living in the United States, Britain, Australia, Russia and New Zealand.