BTW, before signing up for the actual event, you must sign-in (or register) with Trackdayriders. We do this so we can verify your email and keep track of who's signed up for each event.
If you're not a member, simply click the "REGISTER" button on the left menu and create an account. You'll receive an email (usually within 10 mins) with a link to activate your account.
After your account is active, go back to the event page
here, select the day you want, then click the "Register" button. Fill in your info, pay, and you're done. You'll receive another email with a copy of your invoice and instructions for the event.
After your account is set up, you'll never have to enter the registration info again.