I'm currently staying at Bluegelato Hostel. The hostel is run by a super friendly, Koh Tao local called Bom!
Bom will be able to help with anything you need on the island.
He's been v hospitable and he's even looked after my camera equipment, laptops etc.
Bom has become a friend for life.
Would highly recommend visiting this place.
He also rents bikes for 150-250 Baht per day!