Hi cyberg,
Yes, I booked the tickets locally through a travel agent that happened to be owned by the hotel I was staying in. I didn't have any trouble booking or using the tickets. I flew all over Argentina and spent a pittance. Actually, now that I think of it all of the travel agents were advertising cheap fares and packages. In fact I was considering flying to South Africa (being in the southern hemisphere already!) but didn't have the time to make it worthwhile.
I wonder if they have instituted some kind of two-tiered pricing for locals and foreigners since the devaluation? I was there relatively soon after the devaluation. I haven't heard anything about this, though. Please let us know if you can find any more about this. I'd also be curious about your ability to get internal Argentina tickets out of GP. Please post!
Thanks,
Stephen