Although the city of Los Angeles officially recognizes Koreatown as a district, the area has yet to be formally defined by strict boundaries.
(Update: the City Council has since decided on formal borders of a smaller area than what has been referred to as Koreatown by residents. The boundaries are roughly Western Avenue, Wilshire Boulevard, Vermont Avenue, Olympic Boulevard.)
For reference, the most common zip code associated with Koreatown in Los Angeles is 90005.
As an example, the Pio Pico Koreatown branch of the Los Angeles Public Library is located at 694 S Oxford Avenue, Los Angeles, CA 90005.
Other zip codes associated with Koreatown LA are:
90020 – Western Avenue, 6th Street
90006 – Koreatown Plaza, 8th Street
90005 – Koreatown Galleria, Olympic Boulevard
90004 – North Western Avenue
90010 – Wilshire Boulevard, Vermont Avenue
Koreatown Plaza has this address:
928 South Western Avenue, Los Angeles, CA 90006
3790 Wilshire Boulevard Los Angeles, CA 90010
Beverly Soon Tofu Restaurant:
2717 W Olympic Blvd, Los Angeles, CA 90006
City Center shopping mall:
3500 W 6th Street, Los Angeles, CA 90010
3250 W Olympic Boulevard, Los Angeles, CA 90006