I'm going to keep this one short, since you'll go read the article if it's of interest to you.
Another blog for ya'll to check out: http://virginiakantra.blogspot.com/2011/05/write-on-wednesday-pitch-appointment.html
Virginia Kantra is a best-selling paranormal romance writer who also has a ton of great advice for budding authors. This particular article is on giving pitches to an agent/publisher in person, if you happen to be in a place (like a conference) which allows you to sign up to pitch to such an esteemed person. If you're planning on going with a traditonal publishing house, I recommend it. Also, I'd recommend browsing through her other articles, even if you're self-publishing. She's worth the read.