Picton and Tauranga

For the ports of Picton and Tauranga, how close is the town to the ports where the Princess Cruises ships dock (in particular the Diamond Princess in December)? Are there local tours that can be booked at the pier or terminal building?

In Picton they generally dock at the working port and then shuttle you to downtown Picton. From there you can pick up a tour BUT it is a small town so you are much better booking ahead of time or via the ship. There isn't much to do in town.

The port of Tauranga is actually at Mt Maunganui, and walking distance to the town and great beaches.

They generally run a $10 return shuttle to downtown Tauranga. There are generally some tours being sold at the gate to the pier.