I purchased my 4S through Telecom outright last year when they were first released at midnight. Spent the whole day Saturday setting up my new phone and then found out on Sunday morning that it wasn't being picked up in iTunes by my laptop. Thought it might have been the cable but tested this Instore at Telecom with another cable and was still having problems. Tried another computer and same story, so contacted Apple and they walked me through various diagnostics on the phone and a factory reset, which didn't fix the problem. They suggested a return to the store and gave me a case ID which was sent by Telecom to Telegistics who services the phone. After it was assessed, it came back as water damaged, which was ludicrous as i had only had the phone for about a day. I was liasing with Apple Customer Support throughout the entire process and explained to them the situation, they then authorised a replacement to Telegistics who then supplied a new phone.

So I would also agree with Cooper1979 to also contact Apple direct if you have issues with your phone. It will need to be assessed by a authorised service provider here in NZ but it is Apple who will authorise work in some cases like my own situation and also help to speed up the process. Also if you have a case number with Apple it will help to record some of the things also tried in diagnosing the phone, helping to speed up resolution time - helpful when you want to get your $1000+ device back ASAP! ;) :)