Money Is Amazon’s $3,100 stock too pricey? Then try index funds if you want to invest in the market September 14, 2020 By Adam Shell, Special to USA TODAY Comments Off on Is Amazon’s $3,100 stock too pricey? Then try index funds if you want to invest in the market Index funds are diversified mutual funds whose holdings mirror a broad stock index, such as the S&P 500. Here's what else you need to know about them.