I was looking around for the breakdown of gasoline, but couldn't find anything more recent than April 2007.

HowItWorks says 50% of the price is the cost of the crude oil, 28% is the cost of refining, 8% is the cost of distribution and marketing, and 14% is taxes.

Today in my town, gas is $3.50/gallon ($3.499 if you buy a hundred gallons), so that would be broken down (if these precentages are still accurate):

Crude oil: $1.75
Refining: .98
Distrib/mktg: .28
Taxes: .49

Plus a few cents for the station owner.

http://auto.howstuffworks.com/gas-price1.htm

Sue