The ERoEI (energy return on energy invested) is a hard stop fact of life.
The required energy investment to extract a barrel of crude from shale or tar is far, far higher than so called "conventional" resources. When oil bubbles up from the ground, one needs to do little more than provide collection, refining and transportation facilities to bring it to market.
In such a scenario (rare these days) the ERoEI is as low as 1 barrel in to 100 plus out...in other words you will burn one barrel of crude to get 100 or more out...a good deal, but one hard to find these days.
Extraction of the shale or tar sand types requires massive inputs of both natural gas and water, both of which are typically in short supply where shale and tar deposits exist. More bad news, the quality of the oil will not be nearly as good as the 1/100 type. Such oil that is recovered will be of lower grade (heavy/sour, not light/sweet), meaning that a lower volume of top distillates like gasoline and kerosene can be refined per 42 gallon barrel.
Much the same applies to deep water discoveries. The cost of extraction for deep water is far higher than land-based deposits, and the oil quality for these new discoveries tends to be shit compared to what it used to be even a few years ago. Deep water drilling rig costs are going through the roof right now.
There's plenty of oil out there.. but part of the reason your gas prices are going up and up is that the oil quality is crap now, and it will take a major investment to re-jig existing refineries to process crappy oil.