Where is a good place to find reliable statistics and/or historical sources about USA?

US Census. . . Just to start.

start with this wikipedia article, click on each of the main article references, and pick any of the references listed at the bottom of the article.

Your local library. There are almanacs and statistical books on the US for just about everything under the sun. And government decennial census data is available going back to 1790.

US Department of State and the CIA Factbook which are both online. MIT has some excellent free course materials in all subjects, including American History, etc. UK has it’s Foreign Ministry site. It would be interesting to see what they are saying about us. (~Or would that still be the Colonial Office?) I would access the Aussies and Canadian Foreign Ministry information sites to see what they have to say as well. World Book Almanac. Wikipedia will lead to an unlimited amount of related links on every subject concerning the US, especially if you take the States on a state-to-state basis. Encyclopedia Britannica. I would access any countries’ sites for which I could understand the language. That should get you started and lead to many other sources and links and hours and hours of surfing.

Keep in mine that the USA is not the centre of human civilization nor does it represent the highest form of human life. Despite its own self-aggrandizing propaganda, Americans need to evaluate where they really fit in the world. They could set aside their dogma about being the greatest country in the world. That is both false and irrelevant!

I would try BBC.com I wouldn’t try any American sites as the “findings” are usually tainted with political propaganda. It’s really hard to break away from that.