It’s possible to book the ticket at http://www.scandinavian.net – but be aware that the capacity is rather limited so if you want a good price you need to book the ticket 6 months in advance. There are last minute tickets available too but my impression is the prices are somewhat higher.

I’m sure you’re familiar with the circumstances of the place? Svalbard is one of the few places on Earth that you can go to by way of regular scheduled flight despite the fact that you really need to be educated about the circumstances of the wilderness up there before going for your own protection.

One of the times I was up there I met a guy from Spain who had gone there on a whim. He was camped in a toy tent up against the service building in the camp site and he didn’t dare walk the 3 kilometres to town. He had only learned upon arrival that there were polar bears roaming freely up there and to put it mildly his clothing were not warm enough for the place either. I wouldn’t want that to happen for you.

Mind you the place is civilised enough that if you have a well padded international credit card it’s possible to hail a cab, get a bed, bath and hot meal in style.