I would not recommend shipping a laptop from the USA. If needs be, I would go with the suggestion above - get someone to bring it in their luggage. Incidentally, what laptop spec are you looking for. They can generally get you anything here if you know the right PC shop to go to?
Fin, I'm buying a Sager Np8660 Laptop. It's the only 15.4" laptop in the world with a Geforce 9800GT (at the moment). It's based on the Clevo chassis and it's rebadged and sold by brands like Sager and Eurocom. So far I haven't found any laptops approaching those specs in Vietnam but if you know of any let me know. Other requirements are a 300GB+ 7200 rpm hard drive, 2.5Ghz p9500 Core 2 duo processor and all the bells and whistles you'd expect for $3000.
Thanks for the advice!
I have to go with what Finnmaccool said -- would recommend not getting it shipped here. It can be a nightmare getting it through customs and the like. (Yes, I speak from experience, and it was not pretty.) If you do end up deciding to ship it anyway, make sure that when it arrives you bring someone with you who speaks fluent Vietnamese (preferably, someone who IS Vietnamese) because there will be a lot of paperwork and other general procedures, and they won't speak much English.
Good luck!