   Video Game Sales Statistics
  Does anyone know where I can get statistics on video game sales?  The "NPD Group" looks to have some info but there is a price attached (more than I''m willing to pay for a just an school assignment).  Any academic studies?Thanks! 
Gamasutra have some sales figures - they just put up the Developer Salary Survey for this year, and they report the weekly top 10 sales charts for the US, UK, and Japan. 