For investors heavy into oil and gas stocks, the news from the Energy Department this week couldn't have been better. Crude inventories are lower than anyone thought. Demand for crude this year and next is going to be higher than expected. Oil prices are rising again.

For long-term investors cursing themselves for not getting in this game sooner, the situation is a bit dicey. There are no bargains in the oil sectors anymore, at least in the sense of traditional value investing. Seven independent oil companies are trading at more than 100 times earnings. In the services and drilling sectors, companies below triple-digit PEs tend to go for multiples of about 20 to 40. YCharts Pro finds almost all of them overvalued.

And if you're attracted to major oil companies, you'll find the market cap of Exxon (NYSE: XOM) and Chevron's market cap (NYSE: CVX), too, have ballooned in recent months.

It's probably best to just man-up and pay the price. Like it or not, oil and gas will be the food that feeds the world for years to come, and demand for it will only rise when economies really recover. There's not much point in debates over which kind of oil company will make the most money for investors either. Really, it would be nice to own a piece of them all.

So we're sifting through the more than 200 drillers, independents, service companies and majors YCharts lists to find companies from each of these sectors worth picking up now. The drillers got grilled first, since they're seeing the most action now. We'll dig into the other sectors in later columns. Investors in drilling and exploration companies got the bragging rights for recent gains. Shares of several of them jumped in the past few weeks as crude prices rose.

Patterson-UTI Energy Price Stock Chart by YCharts

The drillers are the contractors of the industry, the workhorses hired to dig the hole where the operator points. Like everyone else in the industry, they're busiest when oil prices are high, as they have been in the past year. Still, it's an expensive business, which means the balance sheets of many of these companies are not particularly strong. But Patterson-UTI Energy (Nasdaq: PTEN) has been a stand-out, reporting growth while maintaining decent fundamentals. Revenues about doubled from a year ago, and earnings began to follow.

Patterson-UTI Energy Earnings per Share (TTM) Stock Chart by YCharts

PTEN's books are stronger than competitors in part because its costs are lower. The company works mainly on land; jobs that typically are less problem-prone than those deepwater operations. Here's a look at PTEN's operating margins compared to a few competitors.

Patterson-UTI Energy Operating Margin (TTM) Stock Chart by YCharts

Investors already jumped on the PTEN bandwagon. But its P/E ratio is running at about 26, which believe it or not is about mode-level for the sector. PTEN is not the cheapest play in the sector or a sure thing. But its strong balance sheet gives it strength to handle the volatility in investing in a commodity-dependent business, and it seems to be on a roll with customers. If PTEN can continue to do this...

Patterson-UTI Energy Price Stock Chart by YCharts

... for even a little longer, today's share price will look like a bargain.

Dee Gill is an editor for the YCharts Pro Investor Service which includes professional stock charts, stock ratings and portfolio strategies.