A friend sent me this. If you're interested in "Buying American" this might help. Don't know if it is good in other countries.
HOW TO READ BAR CODES
ALWAYS READ THE LABELS ON THE FOODS YOU BUY--NO MATTER WHAT THE FRONT OF THE BOX OR PACKAGE SAYS, TURN IT OVER AND READ THE BACK---CAREFULLY
With all the food and pet products now coming from China, it is best to make sure you read the label at the store and especially Walmart when buying food products. Many products no longer show where they were made, only give where the distributor is located. It is important to read the bar code to track its origin. This may be interesting to know when grocery shopping if it's a concern to you.
If the first 3 digits of the barcode are 690, 691or 692, the product is made in China.
00 - 09 ...USA & CANADA
30 - 37 ... FRANCE
40 - 44 ...GERMANY
471 ... TAIWAN
49 ... JAPAN
50 ... UK
UPDATE - According to Snopes the numbers cannot be strictly relied on to indicate source. An item may be grown in Chili, but processed in Mexico and would show a Mexican bar code. So, take this list with a grain of salt.