Oracle, AT&T, and Baidu are all undervalued blue-chip tech stocks.Some investors might think that $3,000 isn't enough cash to get started in the market, especially when some popular stocks already cost hundreds of thousands of dollars per share. But now that most brokerages offer commission-free fractional trading, it's fairly easy to build a diversified portfolio with just a few thousand dollars.That said, investors with limited resources shouldn't hastily chase the highest-growth stocks. Instead, they sho ...