My question is basically, how much crude oil is required to produce a
given volume of fuel grade ethanol, as compared to the amount of crude
required to produce the same volume of gasoline.

Obviously, crude oil is required as a raw material in the production
of gasoline, but what are the other energy costs assocated with
converting that crude oil to gasoline. In comparison, what are the
energy costs associated with the production of ethanol for use in
ethanol blend fuels. Not only the actual cost of conversion from grain
products to actual ethanol (including, but not limited to, costs of
energy to operate the required conversion equipment), but also the
energy costs associated with growing, harvesting, and transporting the
grain to the refinery. I had read a report about the number of barrels
of crude oil it takes to produce a cow (surpisingly it was 4+), which
included the costs of petroleum-based fertilizers for feed grain,
costs of transportion of the grain to cattle facilities, costs of
transportation of cattle to slaughter, etc.

My end goal is to know, from a resource cost standpoint, the benefit
of the use of ethanol blend fuels.

This is an old (1995) study, but you may find it interesting:

http://www.ethanol-gec.org/corn_eth.htm

According to the Minnesota Dept of Agriculture, the current energy
yield for corn-based ethanol is 1.34 (you get 1.34 Btus of energy out
for each Btu of fossil fuel energy used to produce it). A lot of the
fossil fuel used is in the form of fertilizer, which is made from
natural gas rather than crude oil.

If you make ethanol from cellulose (raw biomass such as straw, grass,
or corn stover) the energy yield is much higher, around 4-5 Btus
produced per fossil fuel Btu used. However, the conversion process is
more expensive, so this source of ethanol is still uncommon.

For gasoline the yield they list is 0.805 (in other words, about 80%
of the total fossil fuel energy that goes into making it is still
available in the final product.) However, the yield per barrel of
crude oil is much lower, because you can only refine out the amount of
gasoline present in the crude (which also contains many other
substances, including methane, propane, kerosene, lubricating oil,
paraffin, tar.) The average amount of gasoline present is about half
the volume of crude oil.

You also may want to figure in the transportation cost to get the fuel
from the production facility to your gas tank, which could be halfway
around the world for gas or several hundred miles for ethanol. In the
US, ethanol production is concentrated in the corn-growing states in
the midwest.

http://www.mda.state.mn.us/ethanol/balance.html
http://www.ems.org/biomass/intro.html