I should be there, too.
Make sure you get there early (before 8am), even if you plan to 'just' check it out. I'd planned to do the same thing the first time I went up to Alameda back in May, about 2 weeks after I got my CS, and the next thing I knew I had on a club-supplied helmet, and had Brad sitting beside me guiding me through my first autocross. But also beware, I've been to nearly every autocross I could get to since!!
It really is very easy and safe and you can drive at whatever speed you are comfortable with, there's no minimum speed limit! It's also safe on the car, the only thing you are likely to do is wear your tires out a bit.
Check out the
FAQ on the GGR site:
http://www.pca-ggr.org/show.cgi?id=autocrossinfo and some of the site's feature
articles on autocross:
http://www.pca-ggr.org/article.php .
Cheers,
John.