I don't know if this could be helpful to you guys... but here I go.
I was looking for an IP landline in new zeland, that can be used overseas of course, that way I will leave my familiy with a NZ phone here in Chile, I stumbled with 2talk.co.nz, I registered yesterday, they have a free account, It provides a from de cellular range in there, so I can be called, free on my side, cellular rate at the caller side.
It can be used from your computer with a softphone they provide, or from a VOIP gateway, IP phone, gsm/wifi phone ( like my Nokia N80), if you are not that much o a nerd...(like me) stay with the softphone.
The difference with skype or other is that they don't provide NZ numbers ( if I'm wrong correct me please)
Other thing I found out is that I can configure call forward on my new NZ number, and it rings on my landline here in Chile, free of charge on my side, so I will put my 028 number on my NZ resume, that way it doesn't matter if I'm loged in to their service, I will receive calls anyway, it is supposed to work call forwarding to a cell phone too, it didn't work for me, I don't know why, but maybe it could work for you.
You can get local numbers too.