Google provides the facility of GOOGLE FINANCE from where you can easily pull important stock data in google sheets to track your portfolio.
I have explained how you can create and track your stock portfolio using google sheets here: http://www.tradebrains.in/track-your-stock-portfolio-in-google-sheets/
Note: This sheet is useful for small investors who are not involved in frequent trades and just want to keep a proper track of returns and dividends. The current stock price gets auto-updated as the prices are pulled from google finance.
I hope it helps. Happy Investing!