The Family Search Beta Site has a nice user friendly search for the 'Library Catalog' search select Place names under Search and in the For box. I typed in Samoa. I got a list of film records for Samoa.
Here's some of the hits from this search that we've already ordered the film
Samoan Mission Membership Files Early-1955
Record of Members 1881-1951
Marriage records for Upolu 1919-1993
Check it out there is a lot of information...Link to site