Craigslist is probably a good idea, but I never check it! I don't generally find the sellers in Chungmuro so helpful, although I do like Saeki P&C. There is another shop with a reasonably helpful owner, but I don't know the name. There's also the Mozart cafe which is a shop / camera museum of sorts / nude photography mini gallery. You have to order a coffee (invariably terrible) if you go in and want to look around. It's worth it if you like old camera gear.
I did see 35mm and 6x7 enlargers for sale in Chungmuro, but I shoot 9x12, 10x15 and recently added 13x18. I have a feeling that if I found a large format enlarger here it'd cost quite a bit.
I studied Korean at Sogang university for 9 months which helped a lot, but even after that my language skills are depressingly basic...
NT, about my light source...it's quite a simple affair, a bunch of fluorescent light tubes grouped as closely as possible in a box with a couple of layers of perspex (one white, the other transparent and scuffed with sandpaper) for diffusion. Getting the diffusion to work well enough took some trial and error, I tested it as well as I could with a spotmeter. I use a film pack adaptor as a negative carrier, the film pack adaptor is attached to the light box and it at least clicks into place in the camera (Zeiss Ikon Ideal 225) minimising alignment problems in that area. Sometimes I mount the whole thing on a tripod, but aligning it completely accurately feels nigh on impossible (I don't let such trifles get in the way, I have bigger problems with my prints!). I could rig a way of aligning it better with a wooden box or something but haven't got around to it, it's the sort of thing that's evolved slowly. I don't recommend this sort of thing in place of a regular enlarger altogether, but it allows me to make decent enough prints while away from home.