Most investors don't keep tabs on their companies' fundamental values. That's a mistake. If you take the time to read past the headlines and crack a filing now and then, you're in a much better position to spot potential trouble early. Better yet, you'll improve your odds of finding the underappreciated home-run stocks that provide the market's best returns.

We can help you keep tabs on your companies with MyWatchlist.com, our free, personalized stock-tracking service. Here are three dividend stocks for your watchlist.

1. Sunoco (NYSE: SUN)
Similar to Marathon Petroleum (NYSE: MPC), Sunoco is a refiner, with operations across 24 states. What makes Sunoco special is that it also has large amounts of midstream assets, with 7,600 miles of pipelines, as well as roughly 40 active terminals. The stock has done poorly the past few years and has traded in line with the market this year.

But things look like they may change. Last week, management hired Credit Suisse to consider strategic options to boost shareholder value, including a sale of all or part of the company, conversion to a master limited partnership, or an expansion of one division. Corporate actions are a great place to search for value, and analysts from Barclays believe the company is worth $48 to $58 per share in a breakup, well above its current level below $38. While you are waiting for the shares' value to be unlocked, shareholders have the added benefit of a 1.6% dividend. It's always nice to be paid while you wait and this is a story certainly worth watching.

2. CAPS' Weekly Top Stock Idea: Silver Wheaton (NYSE: SLW)
Each week, I cull a top stock idea from the pitches on CAPS, The Motley Fool's 180,000-member free investing community. Silver Wheaton, a pick from December, caught my eye, since its shares have risen 24% over the past three months compared to an 8% drop for the market. Silver Wheaton, along with fellow silver companies Hecla Mining (NYSE: HL) and Silvercorp Metals (NYSE: SVM), are focused on the production of silver. While the company doesn't pay a large dividend, $0.12 for a 0.3% yield, the fact that a silver company is confident enough to pay a dividend says loads about its prospects.

With long-term contracts for silver at $4 an ounce, Silver Wheaton is profiting wildly from the rise in silver prices over the past year. Former CEO Peter Barnes said before he left, "I don't see any reason why in the future we couldn't be paying out 40%, 50%, or 60% of our cash flow every year in dividends." As the company's current free cash flow payout ratio is just 9.5%, that would be a big increase. See the pitch selected for CAPS' weekly top stock idea. If you want to follow my weekly picks, you can subscribe to the series' RSS feed or follow it on Twitter.

3. Cliffs Natural Resources (NYSE: CLF)

As the seventh best performing dividend stock so far this millennium, Cliffs Natural Resources should already be on your watchlist. If you are unfamiliar, Cliffs Natural Resources is a large producer of iron ore and met coal from North America and Australia, with iron ore making up nearly 90% of the company's revenue. In fact, the company is the largest producer of iron ore pellets in North America. In addition to operating its own properties, the company also operates mining operations for royalty trusts including the Mesabi Trust (NYSE: MSB).

The company has been benefiting from China's massive economic growth, which requires large amounts of steel. Iron ore and met coal are key components in steel, and as such, Cliffs is raking in the profits because prices for the two commodities are at highs. While some investors are worried China's growth is going to temper off , I believe the concerns are overblown. While the stock is richly priced, were the shares to drop significantly in a global sell off I'd certainly consider buying shares. The shares have the added bonus of a 1.4% dividend.

My Foolish bottom line
Consider these three stocks along with the 13 names in a free report from The Motley Fool's expert analysts, "13 High-Yielding Stocks to Buy Today." A senior retail analyst dubbed one of the picks as "the dividend play of a lifetime." Tens of thousands have requested access to this report, and today I invite you to download it at no cost to you. Get instant access to the names of these 13 high-yielders -- it's free.