I'm pretty interested in seeing demographic data as I find them good targeting tools. But other than the ESA reports (free) and NPD numbers (paid) does anyone know any other sources for such data?
Here is a website that has very interesting demographics regarding MMORPG's in the US. http://www.nickyee.com/daedalus/gateway_intro.html
This is from the same site but it has a bit more general data. Just keep clicking the small "Next Page" link at the bottom for more statistics including Good vs Evil, Choosing a Race, and etc. http://www.nickyee.com/daedalus/archives/001558.php
Here is a slide show on demographics for teen and adult gameplay in 2009 http://www.pewinternet.org/Presentations/2009/11--Cheats-for-Video-Game-Marketers.aspx
This is another site that has demographic data on game developers which is useful for those developing an SDK or engine. You can also submit a survey to help improve these statistics. http://archives.igda.org/diversity/report.php
If you are looking for specific demographics you could also try picking up the phone book and calling major players in the game development realm. For example, I am sure Microsoft will have no problem giving you demographics on its specific users. Hope this helps.
Not free, but you might want to talk to EEDAR.