(Undated) — The national average for a gallon of regular unleaded has fallen over the last week. According to this morning’s numbers from GasBuddy.com, the national average is $3.07 a gallon, down nine cents from last Friday. Here in Illinois, drivers are paying an average of $3.24 a gallon, nine cents lower than a week ago. Across the river in Indiana, the statewide average is $2.90 per gallon, a fifteen-cent decline from a week ago. Oklahoma drivers are paying the lowest statewide average $2.55 a gallon, down three cents from last Friday. Drivers in California are paying the highest at $4.65 a gallon, up a penny from last week…