My question relates to transportation between the beaches. We will be visiting the following beaches in this order: Khao Lak, Phuket, Krabi and Koh Lanta. What is our best bet for transportation between each location? Should we book this prior to our trip or can we do this easily in each place - either through the hotel or local resources?

It will be easy to book each leg as you go. There's always a "Travel agent" or "Tour Operation" that will gladly provide this type of transportation. Often it is in a minivan. By waiting until you get there, you will save 50% or more. Booking through the hotel or pre-booking with an international travel agent will cost a lot more.

Wow, thank you. That is great to know upfront. We had planned to have a travel agent book transport for us but now we will certainly wait until we're there.

Just look at the various stores in the commercial district. They will have signs for tours, etc. inquire within. I do note that Ko Lanta may present more of a problem. It is somewhat isolated. I'm sure someone will chime in with suggestions.

No need at all to book anything upfront. From Phuket take the ferries via PP Islands - Koh Lanta - Krabi.