So I was looking for sample data to add to my SharePoint site so I can practice on creating different kinds of google charts. I came across this site, fakenamegenerator.com, which can generate data for you. I also found this site too, Contextures. It does not give you a lot of data but enough to play with. Hope it comes in handy for you.
Anyway, look out for my post in the next couple of weeks on how to use google API, spservices and jQuery to generate different kinds of charts. Stay tuned! 🙂