Sanam Maharjan

This is a plugin for converting lots of posts or pages to a custom post type (or vice versa). In the ‘convert from…’ select option you will get the lists of all the post types stores in your current database and in the ‘convert to…’ option you will get the list of all the current registered post types. In addition to this you can also convert from one taxonomy to another and the lists are populated just as that of post types.

Post Type Convertr

A bulk conversion utility for post types and taxonomies.

Amaury Balmer

WordPress 3.1 and up allow to manage new custom post type, this plugin makes it even simpler, removing the need for you to write any code. Excerpt update your theme !
This plugin provides a nice interface and easy access. The plugin provides almost all the parameters of the WordPress CPT API.
It’s possible to manage the permissions of custom post types such as articles or pages. Or create a full set of custom permissions and related roles !
This plugin is developped on WordPress 3.3, with the constant WP_DEBUG to TRUE.

Simple Custom Post Types

WordPress 3.1 and up allow to manage new custom post type, this plugin makes it even simpler, removing the need for you to write any code.

Post Type Convertr vs Simple Custom Post Types