Hej Björn!

I have booked and paid a ticket ex Tonga, but only with Oneworld. Organising a *A ticket would probably be a very similar process. I have basically done the following:
1) Planned my route to make sure that it met RTW ticket t&c
2) Called the Polynesian Airlines office in Nukualofa
3) Got their email address
4) Emailed the itinerary
5) Called to make sure that all flights were available and get the total price
6) Checked in www.checkmytrip.com to verify the booking
7) Faxed my credit card details with an authorisation of payment
8) Fly to pick up my ticket (you can probably get it mailed)
9) Fly back to Australia as first leg of my itinerary

I will do point 8) with an award flight and point 9) above next month.

Unfortunately, the OW RTW fares ex Tonga have increased around 50% since 15 June 05, so there is no longer an advantage to buy a OW ticket ex Tonga. I only just scraped in before that date to save AU$3000 for a DGLOB34. Next year I will fly *A for sure, unless they hike up their fees as well.

Lycka till!

PS. I've got 33,987 miles on my itinerary. 13 miles spare for DGLOB34!