Admin Username Changer for WordPress
Secure your wordpress blog by changing your administrator username. By default the administrator username in wordpress is “admin” which makes the job easier for hackers, they only need to find out the password. Now, you can change the default admin username to your liking. No one will know it and that improves your site security greatly. This plugin inserts a menu option in admin menu for changing the admin username.
To add this plugin just go to your your WordPress Dashboard>>Plugins>>Add New and search for Admin username changer and add it, and then activate. Otherwise download it from the link bellow.