Is there a way to find out how much of a product is sold in a year?

-for example,

how much wii was sold last year



is there a website for this tracking?Consumer Reports is good for tracking stats like that, also Popular Science may have run an article tailored to those questions. Many other magazines will too. Titles of articles can be looked for in the Readers' Guide to Periodical Literature in the library or on line. Also, who tracks the wii would be Nintendo and other mfg.