Although it is possible to find work without visiting New Zealand, many new immigrants have not been employed while still being overseas. Although there is a shortage of skilled workers in New Zealand, the majority of employers prefer to meet face-to-face with prospective employees.
Please be aware that the reputable and professional recruitment agencies will be more likely to market your skills to prospective companies if you are willing and able to attend interviews. This does not mean that it is impossible to obtain meaningful employment, as Skype interviews are always an option.
Although the job hunting process can start in your home country, you should always be willing and able to do whatever is necessary in order to obtain a job offer. Think about it this way, would you be more willing to employ a candidate who you have met in person or one you haven’t?