JOEL - There are only two circumstances where a member needs to be rebaptized into the Church:
1. After excommunication
2. After voluntarily asking their name to be removed from the church.
You need to talk with your current Bishop about your situation to find out what needs to be done. As long as you have not committed any sins that would justify excommunication, and your name is still on the records of the church, you are still a member and do not need to be rebaptized; although you may still want to re-learn what you have forgotten as you are now doing. When you change your name, you simply need to tell the membership clerk of your current ward, and he will take care of reporting the name change for you.