A guy I knew shipped all of his stuff (he had a wife and baby so he had a lot!) by a shipping company but I can't remember the name. I think for around 1,000,000 Won he got it shipped to his doorstep. That's the way to go if you have lots of stuff. If you just have a few things, the post office might be your best bet. I mailed about 12 boxes home a few years ago. It was about 25-35,000 per box...
if you find a shipper let us know. i will need one in a few years.