à lesund is full of restaurants, and you can generally find anything for whatever taste you might have.
For cheap food, the town has quite a few pizza, kebab and burger shops. Next to the town square you will find Dolly Dimples pizza, a few meters away you will find Peppes Pizza and the local McDonalds restaurant, as well as a 7-eleven that is open 24/7 and sell hot food. You can usually get food for around NOK 100 in these restaurants.
For more regular restaurants, you have choices such as Hummer og Kanari Kongens gate and XL Diner Skateflukaia. XL Diner is the largest clipfish/bacalao restaurant in Northern Europe. Expect to pay a minimum of NOK 300.
More upmarket restaurants include Sjøbua, a somewhat famous seafood restaurant, where all food is prepared from the local fishermen's catch of the day. The fish is kept in tanks in the restaurant for maximum freshness.
In general, if you're out in à lesund, you should make sure to try the local seafood dishes. It is the centre of fish exports in Norway and has a unique tradition is seafood cuisine. Clip fish is a local speciality, and a dish that locally is known simply as "bacalao" is a favourite not easily found in other parts of the world.
Do note that wine is usually quite expensive in Norwegian restaurants, charging 300 NOK or more for a bottle of wine is not uncommon.