Have started a stud book for a sim I play on, people fill out a form, the details get sent to my email address, and then I add the entries to the site.

However, this idea has taken off faster than I had imagined, and I don't have enough time to add all entries.

Rather than limiting the horses that come through the form process, I was hoping someone here could advise me on how to produce a site based on the guestbook.

Basically, the person would complete all parts of the form, and once they click submit, their form would appear immediately on the page.

Is this possible?

Erm...Yes, I have seen it before. I think its at http://www.christinafan.com/~come. I don't know how you do it though. You'll have to ask the webmaster, and the last time I went there it was Char - http://www.tainted-dreamz.net.
I hope I helped!

Sorry to be slow [is IS Sunday after all] but how does a Christina Aguilera site help me?

What you want to do uses MySQL. Try searching in google or something for MySQL. I hope I helped!