Is there a way to have a content type that is only viewable to admins AND the person who created it, including comments? I feel like I know the answer to this but its escaping me.
If the content type is defined by your own module, you can use hook_access to do this.
If the content type is defined by CCK or another module, things are a bit trickier. You can install a patch that adds an access op to hook_nodeapi, but unfortunately that's a hack to the core Drupal code, with all the potential upgrade pitfalls that ensue.