What changes has the oil industry seen since the 1990's?

I'm doing some research on oil prices (more importantly, gasoline prices) in the late 1980's into 1990 as well as the changes in demand and the amount of supply the oil companies have and the capability they have to acquire more (any innovations in drilling, new found wells, etc). Any sort of legislation in the U.S. and abroad that have shaped what the industry is today as well the reasoning behind the legislation would also be very helpful. I'm also looking for all of this information in today's market as well. I trade commodities, so please do not simply give me prices without a chart. Other than that, any information you can provide me with would be great even if it only moderately pertains to the subject. The more information, the better. Links would also be a huge help! Thanks in advance.