Berkshire Hathaway Warren Buffett's letters to Berkshire shareholders explain what makes companies tick. Articles, a giant glossary, and a huge list of links to other sites. Smartmoney Articles and lots of very clever interactive gadgets. The Roth IRA Stock Valuation Sites to Research Specific Companies and Stocks Marketguide offers one of the best and most convenient summaries anywhere, with all the important fundamentals on one page. This is the first place to go to research a stock.
News sources are available all over the place.
Quicken is a good representative. Online tax forms, and financial advice. The SEC is committed to making the market reliable and protecting investors from abuses. Their site has a lot of educational material.