Instructions
Check out the Noritake listings on replacements.com. If you know the name of your pattern, you can open up a link to a replacement and see the date the pattern was made on the upper left hand side of the listing.
Purchase a book detailing the history and value of Noritake china pieces. Noritake recommends "Noritake: Jewel of the Orient" by Bob Page, Dale Frederiksen, and Dean Six, "The Collector's Encyclopedia of Noritake" by Aimee Neff Alden and "Early Noritake China" by A.N. Alden and M.K. Richardson.
Visit an appraiser recommended by setyourtable.com, which is recommended by Noritake. To have an appraiser give you the date and value of your china, you'll have to pay a fee.
Drop by a local antique emporium and ask if there are any experts in old china available. If someone is available, show him a picture of your Noritake china and ask for his opinion.