My guess is that the giant urban cockroaches in American Samoa are American Cockroaches. The name “American” stems from the fact that Linnaeus named the species based on a specimen received from the New World, they are native to Africa. This species is now distributed worldwide where it thrives in and around human habitation. There are probably many pictures available of this insect since it is a pest species. You should try a good search engine, such as http://images.google.com for photos.