Will you only be doing roadie riding? Mountain biking in enzed is much better..Auckland(Jaffaland or Dorkland) traffic & public transport is crap . Utter crap is the best word...
Millienz lives in the Auckland region, hopefully she'll see this! Perhaps a nice ride round the Hunuas . (psst...A nice mtn bike ride in the Hunuas )
Where in Auckland will you be staying? If you're staying on the shore biking to the city will be harder.
Check out www.vorb.org.nz & see if someone on the forum can assist!