Jeremy...go here for the basics..
http://www.piscatorialpursuits.com/alaskapage.htm
Also check the search tab above and put in clamming. There was a lot of discussion a few weeks ago.
As for area, don't know about Newport. Haven't been to Seaside or Gearhart which seems to come
forth with your 15 limit. Take what you get -hopefully whole..broken - crushed--
If you've got kids, they each need their own
container.
They will hold about 2 days if you can't get them
cleaned, but keep them in seawater. We have never
put in cornmeal which some people say you need to do. Sand is not an issue for us.
Good luck!