A curious thing is happening among American shoppers. More are checking labels and asking, "Is it 'Made in the USA?'" Walmart, the nation's largest retailer, earlier this year announced it will boost sourcing of U.S. products by $50 billion during the next 10 years. General Electric is investing $1 billion through 2014 to revitalize its U.S. appliances business and create more than 1,500 U.S. jobs.