I think a lot of foreigners use Xanandu Travel
in Itaewon - they cater to foreigners as their agents all speak English. You can make all your arrangements over the phone/internet and they'll just mail you the ticket, wherever you are in Korea. They've been ok in my experience, no major problems.
This is mohammad from Pasargad Territory trip in Tehran - Iran .
I need an agent in korea To let me know , if I want to reserve some hotels in Korea`s cities Like Seol Busan and etc ...What I can do .
Please reply back to me .