It's ok to be scared, just don't let it take you over.

Between everybody's advice here and your mom helping you get ready, I bet you will do great on the interview.

Also, to echo what catnapper said, a thank you note after the interview is a great idea. I did that for the last two jobs I've had (current one from 2002 to now and previous from 1998 to 2002) and in both instances, the bosses said that it was that well written thank you note that made me stand out from the other candidates. My guess is that many people just don't do the thank you notes nowadays.

Good Luck! All fingers and paws crossed for you here!