Sylviah,

This will get you started for sure. http://tonto.eia.doe.gov/oog/info/twip/twip.asp

It is updated every Wednesday (Wednesday is the day when national inventories are announced - about 9:30 AM Eastern - the link is updated later than that tho, maybe 12 noon Eastern?). There are tabs along the top, with a link for gasoline and a link for distilletes. You can look at current inventories in 5 geographical regions and look at past inventories for years and years. It also has price information, refinery inputs and outputs, imports, etc.

Have fun!

North American Fuel Shortage Reports is regularly updated, too. Site running very slowly at the moment though.