how to find Dell computers physical address.

Last December Dell NZ delivered a computer to me that I had previously cancelled. Dell collected the computer and advised I would be refunded the purchase price (thank you!) as soon as it had been received back into the Dell store in Australia. 2 weeks later I had a phone call from someone saying they were from Dell and the computer had been received into the Australian store and I would be refunded shortly. Since then I have phoned the Dell NZ support line (presumably based in Australia)  three times and each time the support person assured me the funds would be credited back to my bank account (from which I had originally paid Dell). Each time I asked the customer care person to email me confirmation: each time they said they would, but never did. Result I have no answerable email for Dell even, and no refund.

What I need now is an address for service on Dell Computers so I can initiate legal recovery of my money. Dell order number is <ADMIN NOTE: Order number removed per privacy policy>

Thanks to anyone from Dell who can help, please. Even a responsive email address for dell would help, as phoning up gets me nowhere except empty promises.