*I'd put my site in maintenance mode before I'd begin.
To remove any unwanted states from ubercart you must first navigate to the folder: (wherever)/ubercart/uc_store/countries/. There you will find a bunch of files that say: "(Harold's_Republic_of_Awesome).cif" - Find "united_states_840_1.cif" and open it up in your favorite text editor.
Next you need to comment out the lines of the undesired states. This is done by placing: // at the beginning of the line. Here is an example of how that would look:
.....
// Make the entries in the zones table.
$zones = array(
array(840, 'AL', 'Alabama'),
array(840, 'AK', 'Alaska'),
// array(840, 'AS', 'American Samoa'),
array(840, 'AZ', 'Arizona'),
array(840, 'AR', 'Arkansas'),
// array(840, 'AF', 'Armed Forces Africa'),
// array(840, 'AA', 'Armed Forces Americas'),
// array(840, 'AC', 'Armed Forces Canada'),
// array(840, 'AE', 'Armed Forces Europe'),
// array(840, 'AM', 'Armed Forces Middle East'),
// array(840, 'AP', 'Armed Forces Pacific'),
array(840, 'CA', 'California'),
array(840, 'CO', 'Colorado'),
array(840, 'CT', 'Connecticut'),
......
After that, log into Drupal and navigate to: Store administration > Configuration > Country settings > Import Country. Scroll down and find United States and click the "remove" link next to it. It will say "Bah..Stuff..errors will occur are u sure?" - Yes.
Now Upload your modified cif file back into the "(wherever)/ubercart/uc_store/countries" replacing the none modified one.
Refresh the "Store administration > Configuration > Country settings > Import Country" page and you should see the "united_states_840_1.cif" in the "Country Importer" box. Select the "united_states_840_1.cif" and click the import button.
Now you shouldn't see the 'American Samoa' 's and or any other //'ed lines.