I started looking at stock market recently and have been getting the finance data mainly from quantmod R package. Besides quantmod, other packages for finance data include: pdfetch, quantmod, tseries, fImport, Quandl, rdatamarket, WDI.
The packages like quantmod provide easy access to data with a few line of codes and make it easier for customised analysis. For example, comparison of a few stocks' within one's portfolio.
I bought SingTel, KepCorp and OCBC stocks recently. Comparing the three stock prices, from absolute value view point, SingTel has the least fluctuation over the last five years. But of course you should also look at percentage changes and other indicators.
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Sample R codes: