Where can I find information on sales figure of Apple products?

I am carrying out some research into Apples product sales over the years. Where can I find information on their sales figures to date? I am looking for information regarding the number of products sold to date, sales of Apple accessories, their market demographic and any other details on who buys Apple products.

If you are looking for a lot of data, I can suggest you take a look at these financial quarter results Apple released themselves:

2012

Quarter 2, 2012
Quarter 1, 2012

2011

Quarter 4, 2011
Quarter 3, 2011
Quarter 2, 2011
Quarter 1, 2011

2010

Quarter 4, 2010
Quarter 3, 2010
Quarter 2, 2010
Quarter 1, 2010

2009

Quarter 4, 2009
Quarter 3, 2009
Quarter 2, 2009
Quarter 1, 2009

2008

Quarter 4, 2008
Quarter 3, 2008
Quarter 2, 2008
Quarter 1, 2008

2007

Quarter 4, 2007
Quarter 3, 2007
Quarter 2, 2007
Quarter 1, 2007

2006

Quarter 4, 2006
Quarter 3, 2006
Quarter 2, 2006
Quarter 1, 2006

2005

Quarter 4, 2005
Quarter 3, 2005
Quarter 2, 2005
Quarter 1, 2005

2004

Quarter 4, 2004
Quarter 2, 2004
Quarter 1, 2004

2003

Quarter 4, 2003
Quarter 3, 2003
Quarter 2, 2003
Quarter 1, 2003

2002

Quarter 4, 2002
Quarter 3, 2002
Quarter 2, 2002
Quarter 1, 2002

2001

Quarter 4, 2001
Quarter 3, 2001

Apple discloses many of these informations with their quarterly reports. You'll find many sources discussing and analysing these by having a quick search in Google, but you'll also find the original announcements on Apple's website.

Have a look at http://investor.apple.com/

A listing of all press releases with quarterly reports can be found on this page: http://investor.apple.com/results.cfm