Although you won't be packing a live fish in your luggage, it's worth taking a look at the Mokpo Seafood Market. Stands that sell the region's popular delicacy, fermented skate, are everywhere, but you can also find dried fish, the catch of the day, and a lot of other wiggly, shiny, wonderful things from the sea. It's open daily from 7am to 8pm.
About a 5-minute walk from Mokpo Station is Carless Street, where the alleyways are closed to vehicular traffic, and you can view your share of boutique shops and open stalls, selling everything from clothing to manufactured goods from the region.
For large-scale discount and department stores, Mokpo has more offerings than most other cities in the Jeollanam-do region. The most popular is the E-Mart in Okam-dong, open daily from 10am to 11pm. You can get there by taking bus no. 10, 13, 20, 105, 109, 112, 119, or 300. They are also building a new mega-shopping center called Formo (short for "For Mokpo"), which will be a megaplex with stores, amusement centers, and a large movie theater.
Note: This information was accurate when it was published, but can change without notice. Please be sure to confirm all rates and details directly with the companies in question before planning your trip.