<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by slawecki:
Grouse, could you please direct me to a way to find the cost of an extra piece of up to 32kg luggage on a transatlantic flight, by mileage, ticket price, or point to point(to or from IAD preferred) or whatever formula is used, as I cannot.</font>
On AA it is on their web site at Customer Service > Baggage > Baggage Allowance. You can also call them to confirm this.
As far as I know Alaska does not fly transatlantic but I am no expert on Alaska.