I collected Seoul map for tourist.
If you visit Korea Tourism Org in Korea, map is a free.
Before get in Korea, I think these map will be helpful to set up Seoul Tour.
Seoul Map in English
also if you want to zoom, visit http://126.96.36.199/hosting/government/knto/ebook_map/ecatalog.php?Dir=1(Required Abode Flash) check page 3.
The above map is easy to read the whole of Seoul, but is not detail.
If you need a detail map of Seoul visit the below sites (required Abode Flash)
I also attached Seoul downtown map in English.