def get_shipping_costs(params)
      raise ArgumentError unless params[:ItemID]
      response = get_json_response(build_request_url('GetShippingCosts', params))
      return response
    end
def get_shipping_costs(params)
      raise ArgumentError unless params[:ItemID]
      response = get_json_response(build_request_url('GetShippingCosts', params))
      return response
    end
http://developer.ebay.com/DevZone/shopping/docs/CallRef/GetShippingCosts.html