The street that leads from the Enoden and Monorail Station just take a left as you walk out of the Enoden station to the beach has souvenir shops and surfer accessories shops. In the same street you will find a Natural Lawson convenience store.
The street on the island that leads up to the shrine has also the typical souvenir shops including a post office and ice cream shops, but the real specialities can be found right when you leave the bridge: grilled and fresh seafood in every variation is sold there. It's a bit like the Tokyo fishmarket in small if you look at all those creatures that can apparently be eaten.
