Hi Jeremy. Are these blogs hosted on WordPress.com or on other hosts?
If they are hosted on WordPress.com, you can either delete them, or transfer them to another user.
If they are located somewhere else (and were attached to your account through JetPack) you can disconnect them by going to the JetPack menu in your site, and clicking the button at the top right that says "Connected to WordPress.com."
If those sites were already deleted from the web host they were on, you can post the URL's of the sites here, and I'll tag this post for a moderator to manually remove them for you.