Your name, your email address, the town you live in, the year / color / engine / body style of your Mustang, and how you found out about the club. If you have a username on the VMF (Vintage Mustang Forum) send that too!
You will need to know the email address you used when you signed up to the mailing list in the first place.
And then look for the link to "Messages" on the left side of the screen.