Regarding this previous post on how to buy a computer in South Korea when you're a bit wary of the meatspace "electronic malls," I found this site: englishpcsales, apparently run by an ex-pat college English teacher like myself. Their selection isn't quite Amazon-level, but it's good, and it seems to focus on high-quality, reputable brands.
Anyhow, I've ordered a new laptop and should get in by the end of this week (3-5 day free delivery in South Korea). The price is, unfortunately, "Korea price" but with free shipping and no tax (that is, tax already included in sales price) it's not that bad.
Using Amazon U.S. for the better sale price and sucking it up to pay the import fee was a bit tempting, but I'm more comfortable knowing I've got a Seoul to Daegu delivery in place (for an "in stock" laptop) rather than a god-knows-what delivery chain from America, and from Taiwan before that.
Honestly, there's no perfect way to buy a computer in South Korea. You can get deals at the big electronic malls, and apparently they'll haggle with you if you can show them a better price online. But chalk it up to a bit of fear of the language barrier and a greater fear of a hard-sell, where a guy tries to offload something lame on me. That certainly happens in America as well but ordering online from a reputable English-language dealer in South Korea felt like the best option, even if it wasn't the cheapest.
Oh, and I paid via Korean bank direct transfer, which has become my go-to method for big purchases. Getting a Korean credit card is a pain, so I don't have one. Getting a Korean bank card (not only easy, but mandatory for foreigners) and doing very fast money transfers is really awesome. The service fee is no more than you'd pay for getting cash out of an unaffiliated bank machine (maybe 1,500 won at most).
And South Korean shipping is generally quite reliable. If my new computer has any problems I'm chalking it up to the manufacturer. (I got a free one-year warranty, natch.)
All that's left to do now is set it up and download Civilization VI to make sure I never have a social life again. (But a little birdie told me Civ V with expansions is better.)