The Maori guy on the TV weather forecast is good for learning place name pronunciations from!!
I work with quite a few Maori groups for an organisation that aims to be bi-cultural & sometimes its hard to tell if someone is Maori or not if they don't start the conversation on the phone in Maori so I've always used the Maori pronunciations.
Where we live (sure its the same everywhere in NZ) the pakeha's - much to my disgust - shorten words to make them easier to pronounce so:
Paraparaumu becomes Paraparam'
and Pauatahanui becomes Pau'tanui
I personally think it sounds awful and ignorant, but what the heck so many people do it! - I just refuse to.
After a year & a half the pronunciations come a heck of a lot easier - although I had to laugh when there was a report on kiwi radio which pronounced Luton airport Lutton - they must have the same problem when they come to the UK!