Books

Māori Made Easy Series
A staple of reo learning that I highly recommend is the Māori Made Easy Series. It progresses the learner in a clear, step-by-step manner.

Raupō Phrasebook Of Modern Māori
I looked at a lot of different books, but found the Raupō Phrasebook Of Modern Māori to be the most useful. It’s not just a phrasebook. It provides a lot of insight into the language, the grammar, sentence structure. I highly recommend it (at least at this point in my learning).