The Picton ferry terminal handles Blue Bridge and Interislander ferries to Wellington.
The ferry terminal has quite good facilities including a cafe (open 8am–2pm daily), storage lockers, vending machines and Wi-Fi internet access (free in the Blue Bridge waiting area, but $2/hour in the Interislander waiting area). There is a complimentary shuttle bus that connects the ferry terminal with the Picton i-SITE information centre and Picton town centre (stopping outside Oxleys Tavern on the corner of Wellington Street and London Quay).
Most car rental agencies have their offices outside the ferry terminal and along nearby Auckland Street. InterCity coaches to Christchurch and Nelson also depart from outside the ferry terminal.
There are also water taxis that connect Picton with various spots in the Marlborough Sounds. Many backpackers use these to get to the Queen Charlotte Track and some of the more remote hostels in the Sounds.
Book Bluebridge ferry tickets here: