post and save vars

before you read on i am a noob, and links will do fine. Im looking for tutorial or an explanation of what to do. Im trying to get an understanding of how to send information to a form, lets say an input field for an email, and have it save and repeat for the next person that fills it out. I guess what im saying is a basic sign up sheet. but this is just an example so that i may learn a starting point.

Thanks
Kent Farst