plugin for “page” with special “post_type”

All pages and posts are saved to the same database table wp_posts, the difference is only “post_type” – “page” for pages or “post” for posts. Is there any plugin, who make a special “page” with a different “post_type”? I would like to get inspired how to do it, for i need to use wordpress for something like “book library” together with posts and pages. I want to have a third “category”, under which there would be only books, it will have a special “create book” page, with a special fields (saved as posts’ meta) , but the database structure i want to keep the same. I will then need to make a special functions for showing books etc.