Note that Presbyterians concentrate on the southern parts of the South Island (the island on the right on this map - Christchurch is just above the "tip" at the middle of the South Island's eastern coast, while Dunedin is at the slight tip far below), meaning that a majority of poeple living in southern South Island (Otago, Invergarcill) are Scottish while the rest of country seems to have majority English descents.
Speaking of practical tourist information, it really depends on a hit and miss manner. Air tickets will always be in the range of at least C$1,500-1,600 range - if I'm lucky I can wait for Auckland-LAX return ticket bargains that run at NZ$1,450 but normally you need NZ$1,900 from NZ. Add NZ$300 for return tickets between LA and Vancouver the "normal" cost is around NZ$2,100 - if you add $100 it is sufficient for a return ticket to London. (This explains curiously, a return ticket to US/Canadian East Coast from Auckland is paradoxically more expensive than a ticket to London despite Britain being farther than New York, Boston, or Toronto from NZ)
A cup of cappucino at a non-chain operated cafe costs about NZ$3.50 now, and if you want to try lamb for dinner at a reasonably posh restaurant at Auckland's Viaduct Harbour, it costs around NZ$26. A main course at the highest end restaurants will cost over $35. If you go to Wellington itr seems a little cheaper. Ethnic eateries cost less: a dish of beef rendang at a fashionable Malaysian restaurant costs NZ$16 and Chinese restaurants typically cost around $17 per dish. Typically, if the food is fresh it is very good but in most cases I think the way it is prepared is disappointing: most cooks can't compare with average-grade French chefs in terms of making a decent and delicious meal.
Cheap restaurants like Denny's do exist, and you can have a steak for about $15. Sounds quite reasonable when you consider a piece of steak already costs about $10.