You can only emigrate to NZ if you meet the entry qualifications (such as possessing skills which are in short supply in the country). So the first website to check has to be this one: http://www.immigration.govt.nz/
If you are serious about emigrating to NZ and you have the right skills and age etc. you may want to consider using an immigration agency who will help you through the process. They will cost you but will save you time and loads of hassle whilst your application is being processed.
There are lots of great things about living here and one or two things that are not so good, but overall we love it more than the UK.