But those searches had come up with nothing.
Until Eddie Dodd and his wife Ros, who live in Geraldton in Western Australia, went on holiday to Canada and the US and someone there suggested he should start a Facebook page.
"I first thought no, but then I finally relented," he said.
It was that relenting which led to him finally meeting the daughter he had never seen.
Social media, along with Mrs Mepham's determination to use it to find her dad, got the result.
Their story is not an unusual one.
Back in 1972, Mr Dodd was 22 and had moved up to Hastings from Christchurch where he worked for a tyre company.
He liked Hawke's Bay and decided to stick around for a while, and he met up with a young lady called Glenys.
She became pregnant - "she had me when she was 17," Mrs Mepham said.
They drifted apart and Mr Dodd made his way to Australia for a year before returning to his home town of Timaru and eventually ended up working in Invercargill.
"They caught up with me there and I started paying child maintenance ... it was $10 a week then."
He said he had no arguments about that as he realised he needed to help his former girlfriend bring up the little girl he had never seen.
His own life moved on and after getting married he and his wife went to Australia in 1985, although they separated three years later.
It was during a campervan holiday through New Zealand with his new partner about nine years ago that he again started asking around and making inquiries but he encountered problems with names, not knowing what they may have changed to, and was advised to go through legal channels if he wanted to try and trace Glenys.
"But we had a schedule to stick to and had to catch the ferry so ran out of time - we couldn't come up with anything."
He said he had always wondered about the daughter he didn't know.
"I knew she was there somewhere but just didn't know how to go about it (finding her)."
Mrs Mepham also grew up wondering about her dad.
"My mum and nana told me different things about him and said I had his personality and sense of humour.
"And I knew he must have been a good guy because he always paid the child support - and a lot of people didn't."
She said she missed him when she got married.
"Mum walked me up the aisle."
She had tried to trace him but was not even completely sure if his surname had been Dodd or Dodds.
Figuring he had stayed in Australia, which he had, although keeping an open mind that he could have moved on anywhere, she searched for Eddie Dodd and Eddie Dodds and discovered "there were thousands of them".
What she did have was an old black and white photograph of him when he was 22 and back in June she made a determined pact with herself.
"I said I will find him."
Knowing he hailed from Timaru she touched base with an online Lost and Found there in the hope someone may spot the picture and recognise him.
It was a long shot, but five hours after she posted it she got a message from someone saying "I think I know your dad".
"I just thought 'oh wow!' - and it all sped up from there."
Social media spreads fast, and the photo was eventually spotted by a relative of Mr Dodd and they sent it on to his newly built Facebook page.
He was stunned to see it.
"I was over the moon and sent a couple of quick emails - but it was difficult to know what to say."
So he called Mrs Mepham, who was thrilled to pick up the phone and hear her dad ... for the first time.
"It was pretty emotional and we talked for 55 minutes," Mr Dodd said.
"We gave each other a quick rundown of what we'd done over 42 years in 55 minutes," he said with a smile.
Mrs Mepham told him that she had a birthday coming up on September 16 - which was one day after her own little daughter Stacey was to turn 4.
That settled the time for the long-awaited reunion and the bookings were made for a September visit.
He and his partner arrived in Napier last Friday and Mrs Mepham went to their motel.
Slightly anxious and not knowing how she would react, or even what she was going to say.
It was the same for Mr Dodd, and they looked at each other and smiled and he simply said he was just so happy, so pleased, to meet his little girl.
"And we talked and we had a drink," Mrs Mepham said, adding she felt no anger because it was just one of those things that happened then.
"I just feel happiness - I'm one of the lucky ones who found their dad."
The emotions overflowed later.
She told children Stacey and 5-year-old Brad that they had a "Poppa" and he was coming to see them.
When they met, they ran up to him calling "Poppy, Poppy!" and the hugs followed.
"That was [a] lump in the throat moment," Mr Dodd said.
He had since gone to visit the youngsters' school and kindergarten, he said.
"Oh they love him and nana Ros - it's just great - and we have such a bigger family now," his daughter said.
Mr Dodd has two brothers and two sisters and has a son and daughter in Australia.
"Lots of new cousins everywhere," was how Mrs Mepham put it.
"It has filled a huge gap in our lives - it's just wonderful," Mr Dodd said.
"And I've been able to fill a gap on my birth certificate now," Mrs Mepham said.
"My dad's on there now and that's pretty cool."
She said the "detective" work across social media showed the power of the medium.
Her advice to anyone trying to find a dad, a mum, a son or a daughter was simply don't give up.
"Just do it - keep looking - it's so worth it."
