Now, there's an interesting question and one I had not even thought of. I had assumed that I would have a cup of coffee or two and maybe a bowl of cereal before heading off to my first tri.
What do you eat befor your normal morning training runs? I have a bowl of oatmeal or some toast and jelly. For a sprint, you don't need to eat much, and make sure that it is something that won't bother you during the race. Drink lots of water, and sports drink. After the race you can eat all you want, my personal favorite is a big doughnut or two.
Don't do anything different than your normal routine. The morning of a race is no time to experiment with a different eating plan. Every day I eat the same breakfast, and I know exactly how it reacts during a workout an hour later...it feels fine. So the morning of my races, I'm eating the same thing. When I go out to Ohio in May, I'm even taking all my breakfast foods with me, so as not to interrupt the routine.