A simple plugin that creates a "listings" custom post type. It is also add a recent listings custom widget, in the widget dashboard.
This plugin is a very simple one. All it does is add a custom post type called 'listing' in the wordpress administrator's area. It also adds a custom taxonomy called "Listing Category" and custom taxonomy (non-hierarchical) called "Listing Tag". Furthermore it add a custom widget which shows the latest listings from the Listing Custom Post Type posts.
The plugin is in English but it can be translated.