The private tour guide we hired in Easter Island was fantastic. Her name is Josie Nahoe Mulloy - she is the granddaughter of William Mulloy, an archeologist/anthropologist from the original Thor Heyerdahl expedition who went on to devote his life's studies to Easter Island and re-erecting the Moai. He is given a lot of credit for reinvigorating the island's cultural heritage and the latter day success with tourism once the Moais were re-erected.

Josie is half Rapa Nui - she grew up in the States and took a degree in anthropology and then an MBA. She worked as an investment banker in San Francisco during the halcyon dot com days, but 12 years ago decided to leave San Francisco and return to her Easter Island roots - she subsequently married a Rapa Nui man and is now well established as a guide.

She highly recommends sunrise at Tongariki (the photos ops at dawn are stunning) and also explores different out of the way places (lava tubes, the peak of the island, etc).

http://lizandrichardsa.typepad.com/liz_and_richard_in_south_/easter_island/

Josie's contact info

Tel - 56.32.100274

Email - haumaka@entelchile.net

Another poster has just recently booked Josie.

There's an accommodation in San Pedro that offers both an ethnical and a cutural tour, very personalized and private. http://destinalo.com/hotels-acomodations-chile/Ckamur-Atacama-Ethno-Lodge

Tito rapa nui tour : tito is a "pure" pascuan. He came to France while young to studio spanish.
He speaks english, spanish, french, portuguese and rapa nui.
We do with him two hikes :
One along the north shore from ahua tepeu to atakena beach
Other around Poike, east part of Island
He do also classic visit by car and had a boat
His website is underconstruction but you can contact him by Facebook or arriving at the Island.
Everybody knows everyone there...
And hiking is easy and you will see a lot that others didn't even imagine it exists
His mail adress is titoatan@hotmail.com
Erik

In San Pedro there are lots (and I mean lots, one in every corner) of travel agencies that organize day tours, some of them are good and some of them are not good at all. I would be quite picky in choosing the agency.
I would recommend staying at Awasi hotel where the day tours are included, they plan where to go and what to see including your interests and your requests, transport, food and beverages are included. The downside is, it is rather on the expensive side but it is well worth it. This is the only hotel I visited there so I cannot comment on the others, but there are other hotels there that offer similar deals, I would trust these more as they are should offer a better guides and better tours.