To find out more about the services and resources available at a particular Family History Center, search the FamilySearch Wiki. 
Here are the direct links to Everett and Shoreline (listed as Seattle but actually in Mountlake Terrace).

To find specific resources at a Family History Center (FHC), you need to search the Family History Library Catalog. The Catalog is “topic- and locality-driven”, and allows users to see if that FHC holds a given book, microfilm or microfiche number.

To search the Family History Catalog for resources at a specific Center, start with the Library Search Page.

1. Select the search type you you want to search (place, surname, etc)
2. Enter the search terms (for places, enter start with the largest category first, e.g,  United States, Washington, Snohomish), 
3. Select ‘Family History Center’ under Availability.
4. Then choose (from a very long list) the Family History Center you want [or click in the selection box and start typing the name; the list will jump to it (for example you can type El and it will jump to El Dorado.
5. Click the ‘Update’ button and you will see your search.