Lachie Hudson and James Mitchell were among hundreds of the weekend's searchers as they beat a path along Batar Creek Road and through the scrub.

The two young blokes from Camden Haven were vastly different to the armies of people clad in high-visibility gear and police uniforms.

But the pair were there for the same reason as everyone else.

"This really hits you in the heart," Mr Hudson said. "This is just a terrible thing to happen to a three-year-old. I mean, I've got a sister the same age."

Like so many others on the Mid-North Coast, the boys had been helping with the search since Friday afternoon when William Tyrell's disappearance became public.

Mr Mitchell said he was searching because he has a two-year-old cousin, "and this is the sort of thing you'd never want to hurt them".

"I really feel for the family, and this is the one thing I could do to help," he said.

The NSW State Emergency Service's Paul Burg spent Sunday organising support from units from outside the region.

The Hunter area sent troops up the Pacific Highway on Saturday, as did units from Forster and the Manning Valley.

More SES volunteers are expected to arrive this morning from as far away as Sydney.

Ensuring volunteers were looked after and got sufficient rest had been essential during the search, and is just as crucial today.

Mr Burg said SES search parties on Monday would include support crews as well as local knowledge.

"Our biggest concern, as with any volunteer organisation, is managing our troops," Mr Burg said. "We've got to make sure they're useful to the search, and looking after themselves."

Inspector Kim Fehon said there will be a briefing from 8am, but volunteers can arrive at the Kendall Show Ground from 7am.

Superintendent Paul Fehon said police were very grateful for the community's tireless resolve through the first two days of the search.

"Members of the public can turn up at any time to register during the day," Inspector Fehon said.