Really depends on what kind of landing page you are needing because they are done in a variety of layouts, styles, and content based features. You can create a new page template by using one of the other templates as a starting point, and perhaps do the rest of the page content from the editor. There are plugins as well that are designed as landing pages, even HTML pages have been used as landing pages for some sites…there are many landing pages built in HTML and then your WordPress site would be in a sub directory..