The most important thing to do is make sure you drink plenty of fluids. There is usually no treatment necessary for a stomach virus. You just wait it out. If it persists, you may need to go to the doctor to get medicine to treat the symptoms.
Don't feed your stomach it will only keep reacting in a bad way. You do have to drink to stay hydrated and it you must eat try dry toast/bread, or crackers. A virus has to go away on it's own. If you get worse then see a Dr.
Unfortunately, stomach viruses are not treated, the symptoms are. Viruses have to run their course, generally a day or two. Severe symptoms need medical attention to avoid dehydration.
