"National Oilwell Varco (NYSE: NOV), a buy in our 'Wildcatters portfolio,' will see an outsized benefit from improving conditions in the global oil market," says Elliott Gue in The Energy Strategist.

"Rig technology is the crown jewel of National Oilwell's business; the unit builds key equipment used on land and offshore drilling rigs.

"The unit is currently benefiting from the boom in deepwater drilling activity -- one of the only drilling markets that continue to see growth.

"Equipment used on deepwater drilling rigs is far more complex and expensive than that used on land or shallow-water rigs. As a result, selling equipment into the deepwater market carries far higher profit margins for National.

"Over the next five years the energy patch should offer some of the best investments around, and one standout is Schlumberger (NYSE: SLB)," says Stephen Leeb in The Complete Investor.

"Schlumberger, by a wide margin, is the best and most dominant. Its services range from well testing to pressure pumping to seismic testing, and it's No. 1 in virtually every area it occupies.

"Some of its operations, especially those that maintain the health of existing wells, are highly recession-resistant.

Energy sector specialist Elliott Gue sees opportunity in Transocean (NYSE: RIG), a leadin player in the deepwater drilling area. Here's the latest advice from The Energy Strategist.

"The market for deepwater rigs, however, has remained resilient and one drilling with direct leverage to deepwater rigs is US giant, Transocean, the world's largest offshore drilling company, with 136 rigs as well as ten under construction.

"Roughly 68 of those rigs are 'semisubmersibles,' and 39 are ultra-deepwater or deepwater rigs capable of drilling many of the complex plays being targeted around the world today.

"What's going on with Transocean (NYSE RIG), the owner of the world's biggest fleet of offshore drilling rigs?" asks Richard Moroney, a specialist in blue chip stocks.

In his Dow Theory Forecasts, he explains, "The shares plunged 67% - nearly $100 a share - in 2008, and we can't blame the usual suspects." Here, he explains why he continues to rate thes stock a "Focus List Buy" in his blue chip-focused advisory service.

"Poor operating performance? Wall Street expects 2008 per-share profits of $14.34, up 68%. Shaky future? Transocean is expected to grow per-share earnings 4% in 2009 and 10% annually over the next five years.

"Fundamentals eroding? Not at all. The balance sheet is sturdy and the backlog stout at $41 billion, or three times expected 2009 revenue. Rather, we see two chief contributors to Transocean's steep slide, and neither should jeopardize long-term prospects.

"Valuations for even the best-placed, most well-established companies in the energy space are sitting at levels unseen since the late 1990s when oil prices collapsed to around $10 per barrel," says energy sector specialist Elliott Gue.

Here, the editor of The Energy Strategist looks at Schlumberger (NYSE: SLB), noting, "The firm active in just about every imaginable market and I regard the company as a top-notch indicator of ongoing trends in the oil services business."

"It's clear that there's been some slowing in demand, and the credit crunch has had an impact on the fundamental business. But the reaction in the stock market over the past three months goes well beyond even a worst-case scenario.

"Bottom line: Many energy-related stocks are pricing in a severe recession and recent action in the broader markets is reminiscent of sentiment characteristically seen near market lows. The short-term outlook for the energy patch is much better now than it was during the bear market in 1998 and 2002.

"I regard Schlumberger as a top-notch indicator of ongoing trends in the oil services business and, more broadly, international oil and gas drilling activity. I always pay close attention to what Schlumberger has to say in its conference calls and, as usual, this quarter's call was instructive.

"One of my favorite indicators for the energy markets is the quarterly conference calls and earnings releases from Schlumberger (NYSE: SLB)," says energy sector expert Elliott Gue.

In his The Energy Strategist, he explains, "In this quarter's call, Schlumberger's management team was notably upbeat, the most positive on industry growth expectations in more than a year. This is a key shift in sentiment that has broader implications for the energy patch at large."

"Schlumberger's reports and conference calls have proved extraordinarily useful in the past for determining the most profitable trends and investment themes. The reason for that is simple: Schlumberger is the largest oilfield services company and has its hand in just about every imaginable market all over the world.

"In addition, the company has traditionally offered long, detailed conference calls; CEO Andrew Gould often relates far more than the outlook for Schlumberger and offers considerable color and detail concerning trends for the industry in general.

"This quarter's conference call was no exception. Schlumberger's outlook this quarter was far more upbeat than in its third and fourth quarter 2007 earnings calls.

Despite the oil market's recent correction / minor pullback, oil remains at an elevated price, and the outlook for the oil and oil services sector remains solid.

And one oil service company worth an evaluation is Diamond Offshore (NYSE: DO).

Diamond is a contract driller of offshore oil and gas wells, with a concentration in deepwater drilling. The company has a strong fleet of floater rigs: dayrates for these rigs will continue to increase at double-digit rates, a market condition that reflects their increased value stemming from higher energy prices, and some pricing power for DO.

Further, Diamond has an impressive geographical footprint (rigs operating in the Gulf of Mexico, North Sea, South America, Africa, Australia, and Southeast Asia) and superior client diversification (51 customers). The Reuters F2007/F2008 EPS consensus estimates for DO are $6.75/$11.89.