see http://koreanovernight.com/realestate for help securing corporate, industrial, commercial, or personal residential real estate.
If you're looking for neighborhoods in Korea that have a good international mix, look toward Samseong Dong, Sinsa Dong, Gangnam, Ilsan, Bundang, Pangyo, and Itaewon. These towns are generally going to be a bit more expensive but they are more comfortable than others.