PALO ALTO, Calif. - Looking for stocks to trust in these troubled times? Join the club. Amid all the accounting scandals and other fraud, getting truly comfortable with an investment is not easy.

When I approached my most cynical sources for ideas, they steered investors to the bedrock of the economy, companies that have been around for decades and survived all kind of markets. And when it came to what to buy now, one theme emerged: Look for companies that stand to benefit from the weakening dollar.

When the dollar is shrinking against the yen, you know something's amiss. But that's the case, surprisingly, considering that non-U.S. investors poured currency into the United States for a decade to take advantage of strong markets here. That meant that U.S. companies that wanted to compete had to slug it out with European and Asian manufacturers who could sell their wares for more lucrative dollars. The tables have turned, making for an opportunity in the wily U.S. companies that have fought those battles.

More stocks you can trust       Illinois Tool Works Quest Diagnostics

Take rock solid Procter & Gamble (PG: down $2.51 to $85.44, Research, Estimates). The company is a global player of good standing, and it's been battling the likes of Unilever forever. Procter's a steady performer in the $100-billion-plus market cap crowd. Its dividend yields a modest but comforting 1.86 percent.

And the consumer products giant has enviable and steady profit margins: In its most recent quarter it earned (that's not EBITDA, cash flow or page views visited) $1.04 billion, up 16 percent from the year-earlier quarter, on $9.9 billion in revenues. At 40 times trailing earnings, the stock isn't cheap. But then it hasn't moved down much in two years.

A similarly built industrial company is earth-moving equipment maker Caterpillar (CAT: down $0.96 to $44.54, Research, Estimates). And relative to where it's been, Cat's stock is cheap. Like P&G, Illinois-based Caterpillar has been an international manufacturer for more than a generation.

It's solidly profitable and is expected to get more so. And its dividend yield -- more than 3 percent -- works out to a whole lot more than your passbook savings. Its multiple: just 22 times trailing earnings.

My sources point out that Nike is continuing to win fans. The company certainly doesn't have the track record of P&G and Caterpillar, but it has been building one, with great management, better brand and solid execution.

The stock ran up recently after a good earnings report, but there's still a lot to like. Nike's (NKE: down $2.91 to $52.76, Research, Estimates) financial statements look like exactly the opposite of a Silicon Valley company's. Profits are increasing: It earned $208 million in its quarter that ended May 31, up 28 percent from the year before, on revenues of $2.68 billion. Its cash balance jumped 90 percent from the year before to $576 million. And legendary CEO Phil Knight bragged about Nike's books being squeaky clean, not the sort of thing a nervous leader would do.

Adam Lashinsky is a senior writer for Fortune magazine. Send e-mail to Adam at adam_lashinsky@timeinc.com.

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