Investors shouldn't unthinkingly follow Buffett, or any other billionaire money manager, into Amazon or any other stock. However, Amazon is a top stock with robust opportunities trading at an attractive valuation, and if you have $500 available today, Amazon is an excellent choice.

Warren Buffett’s Berkshire Hathaway (NYSE:BRK-B) has been quite the aggressive seller of stocks this year. The recent lack of buybacks and extreme level of profit-taking may make some investors nervous.

Warren Buffett has been on a selling spree and recently trimmed his two biggest holdings: Apple and Bank of America. Buffett caught many investors by surprise when he trimmed his Apple position,