Rent a car on the airport, or travel by bus or taxi. Travel by air with http://www.coastair.no.
The Viking Centre.
The Viking Settlement at Avaldsnes is copy of a Viking settlement, complete with a longhouse and all the requisites, has been reconstructed, just below the Church of Olav in Avaldsnes.
In August Haugesund host the Norway Film Festival and The SildaJazz Festival. Check out http://www.freedomnorway.com for information on things to do in Haugesund.
Many things but are extremely expensive :(
There are numerous restaurants on the harbor and we recommend Lothes Mat og Vinhus for the best eating in Haugesund.