I had read about this place on happycow and was here in December 2012. Here's my Ono Gelato review.
It's a cute little shop located in the heart of Paia town. Lots of tourists come here to get their gelato ice cream. One side of the freezer is sorbets that are non-dairy, though I'm not sure what kind of sugar is used to make them. There are around 10 or so flavors from which one can try. A little scoop costs nearly $5, not cheap.
The entire other side of the offering is dairy based gelato.
We shared a scoop of the coconut ginger, and it was alright.