In March, 2005 while travelling from Bangkok to Auckland I was
detained by the Customs Service at the Auckland Airport for over 2
hours. I was interrogated, had every article in my bags gone through,
and finally strip searched before being released. The 3 most important
factors resulting in their mistaken suspicions were that I was 1) an
American 2) coming from Thailand 3) without a pre-arranged hotel
booking. So do yourself a favor and book your hotel before you leave.
Or just skip New Zealand altogether -- you're not really missing
anything.