Why not start now? The sooner you start, the better you will be next year.
Contact the coach. The coach can give you an overview of events, and see which might interest you.
Ask the coach to put you on a training program, so you will be in good condition next year. The coach might even allow you to workout with the current team. That would be a good way to get a feel about which events you might like.
Get in touch with members of the current team, and plan on meeting them and doing group workouts over summer break. If you like distance running, join the cross country team in the fall. Join the winter track team if your school has one. If they don't, join a winter running or track club. If the school has no running / track club, ask the coach to help you organize one.