One thing to keep in mind is that it is impossible to enter this island via a plane. Therefore, you will have to arrive at either Bangkok or Phuket and then take some form of transport, either coach or taxi, until you arrive at the ferry to Koh Phangan. There has been an attempt to develop an airport facility given the high popularity of this location and there are plans underway to create the infrastructure to handle up to 1000 passengers a day.
This would be a brilliant addition to the island given that it receives up to 500,000 visitors each year!
Additionally, when you are on the island, the only form of transport you can count on is the converted pickup trucks called 'songthaews' that function as taxis.