some say oil is a fossil fuel, and the peak of production is not far off. others say it is inorganic and essentially limitless and we just need to drill deeper.
Gold's The Deep Hot Biosphere discusses the inorganic theory. Interesting book by a brilliant guy. Some say he plagiarized the Russian geologists.
Lots of books out now on Hubbert's peak and the other school of thought. Off the top of my head, seems like http://www.lifeaftertheoilcrash.net has a list of links and sources. Some say this idea is a Zionist plot to raise the price of oil.
Oh, no!~ is the Z word verboten in GD? mea culpa in that event