The world is in uproar again, about oil, that is. So, people are digging again for gradually depleting reserves of black gold. The world needs new sources of hydrocarbon fuels, as the demand shows no signs of slowing down and prices of crude oil continue rising. But, finding new oil reserves is proving to be much, much more difficult than it has been in the past.

Familiar Texas landscapes, interrupted only by unseemly oil rigs, quietly and steadily pumping the black gold up to the surface, have become things of the past. These days, you are more likely to hear dynamite explosions, particularly if you live nearby the tough terrain in the Rockies, or smell Mother Nature's nastiness once steam is pumped down bitumen shafts in Alberta's oil sands.

But, regardless of oil's scarcity, regardless of all the risks and costs, the age of black gold is far from over. This is why oil equipment and services companies, those that conduct seismic surveys and feasibility studies, manufacture digging equipment, and especially those that dig deeper and in rougher terrains than anyone else, are doing extremely well of late. In monetary terms, we are talking about billions of dollars in backlogged orders. Experts say there is not likely to be a slowdown in the demand for such services at least for the next three years.

So, who is in demand of such services and who provides them? Well, the world's largest public oil and gas company, Exxon Mobil, is likely to dump $20.0 billion a year on equipment and exploration services. Why? Well, the company needs to expand its portfolio, which is why Exxon is currently juggling 20 new projects worldwide.

But, Exxon is far from alone on this aggressive war path of sorts. There is also Chevron, which also promised to increase its capital spending to almost $20.0 billion on aggressive exploration and development projects. Canadian oil producers are not far behind. Their equipment and service needs are even more pronounced, as exploration efforts intensify in the world's second richest oil resource -- oil sands.

But, I'm not saying you should spend your money on big spenders, far from it. Let's leave all the risks associated with exploration and development to the "frontliners." I recommend focusing on companies working "backstage," so to speak, such as oil and gas equipment and service providers.

They do not depend on how much oil and gas may or may not be on a specific property. They are not terribly worried if crude oil goes through a price correction, though surging prices are good for the business.

All these guys are worried is whether there is a demand for their products and services. And, as of late, the demand has only been increasing. The field is relatively narrow and specialized, and many companies are still privately owned. In the long run, it might pay off to check out names such as Schlumberger Ltd. (NYSE/ SLB) and Petroleum Geo Services ASA (NYSE/ PGS). These two have been rocking lately!