These are books and videos I have come across which offer great insight into te ao Māori (the Māori world).
Recommended Reading
Ka Whawhai Tonu Mātou by Ranginui Walker.
This is an account of Aotearoa New Zealand’s long history from a Māori perspective; rather than beginning with colonization as many historical narratives do, this book begins with the arrival of the early tangata whenua iwi before detailing the arrival of traditional Māori society and then colonization, with many insights into traditional Māori life and concepts. A must read for any New Zealander. Available in many public libraries, thoroughly thoroughly thoroughly recommended.
Treaty of Waitangi: Questions and Answers
A fantastic resource detailing Te Tiriti o Waitangi in depth, produced by Network Waitangi. The latest 2016 version can be read online here.
Legends of Maui – a 1910 book compiling stories of Maaui from around polynesia
Recommended Viewing
Waitangi: What Really Happened
A TV drama filmed like a documentary, reconstructing the events surrounding the Treaty of Waitangi. Great acting and well narrated, this gives a great insight into the minds of some of the major players of Te Tiriti. Available to watch on Youtube in seven parts here.
The New Zealand Wars, James Belich
A DVD series detailing the land wars that followed the signing of Te Tiriti o Waitangi – there are 5 episodes, each 50mins long. James Belich provides fantastic narration and there is an equivalent book as well. The DVDs are available from public libraries and I have a copy of them as well which I’m happy to lend out.
Documentary on Kohanga Reo (Al Jazeera)
An excellent documentary on the origins of the Kohanga Reo movement.
Operation 8
A documentary following the aftermath of the 2007 police raids in Ruatoki and other areas of Aotearoa which wrongly labelled the people of Tūhoe as terrorists. Essential viewing for all New Zealanders.
Recommended listening
1981 Opening of Māori Language Week – Beautiful kōrero from native speakers
Ako Māori 
Kia ora Regan
You may be interested in the Huia Te Reo online certificate for te reo enthusiasts at Te Wānanga o Raukawa. Free to NZ citizens and permanent residents.