RE: Trainer that would eventually lead up to flying a Piper J-3 Cub
welcome to the hobby. first off the nextstar is or another similar trainer would be suitable(search towerhobbies.com). Look at the back of your radio there should be some holes, about 6 close together, give or take a couple. As pierce said, find a club. This will be your biggest step, there you will get instructors with uddy boxes to help you. Then have fun!