As of version 0.4, Ghost supports marking a post as a Static Page. A post marked as Static Page will not be shown in the Blog listing on the home page. After you have created a static page, you can use its URL to link to it in the theme or in your Blog posts. Some Ghost themes support top navigation menus which can be used to link to the static pages.
You can mark a post as Static Page while creating a new post or updating an existing post. To do this, click on the gear icon at the bottom-right part of the page while creating or updating a post, and check the Static Page checkbox as shown below.
You can also do this from the content listing page. Just select the post, click on the gear icon at the top-right, and enable the Static Page checkbox.