Now matter how high oil prices go, investors hoping to strike it rich will need to know where to drill. But some people see plenty of choice spots. Early prospectors hit a few gushers by tuning out the noise questioning last year's big rise in oil prices. Exploration outfits Apache ( APA) and Chesapeake ( CHK), for instance, have rocketed 40% and 67% since last spring on strong commodity prices. Even so, some experts believe the really big energy discoveries are yet to come. "As you know, we like energy stocks -- a lot," Robert Howard wrote to subscribers of his Positive Patterns investment newsletter late last month. "And they have done well for us over the years. But honestly, now more than ever, we think this may be the time for you to overweight your portfolio in the sector." If anything, Howard has seen his optimism rise along with oil prices that, last week, hit a 13-year peak of $38 a barrel. Howard is convinced that cheap energy may finally be a thing of the past. And he isn't necessarily alone. A number of industry experts believe that tight supply and strong demand may keep energy -- and thus energy stocks -- expensive for some time to come.