By plane[edit]
There is no airport here. The closest ones are in Phuket or Krabi. Nok Air offers flight+minivan service from Bangkok to Phang Nga v.v. by flying with Nok Air from Bangkok to Krabi and transferred on a minivan to Phannga. This can be booked directly from their website.
From Krabi airport you do not have to go to the Krabi bus station to get a bus to Phang Nga, as the buses coming from the South pass by the airport on the highway. To catch a bus walk out to the highway (100m), cross over and go about 50m to the right where you will see a yellow shelter on the left side of the road. In May 2015 a bus (big and air conditioned) to the Phang Nga bus station cost 100 baht and passed by at 9:30am after waiting for less than half an hour. Make sure you hail down the bus. Frequency and times unfortunately unknown, so if this sounds too uncertain for you, make your way to the Krabi bus station and get a bus from there (price to Krabi bus station displayed inside the airport was 80 baht).