This site has statistics on international trade and investment for the US. It also reports the national income and product accounts (NIPAs): gross domestic product (GDP) and related measures. There are also some regional measurements, including state GDPs.
This site complies economic, business, financial, fiscal, trade, and exchange rate data for the US from a number of government and private agencies.
A good source for population data, both for historical data and future projections. Also has vital statistics and total fertility rates.
Reports current economic releases in a quick and easy to read table. Also, shows a timetable of future releases.