There are plugins that lets you customize admin bar like you can remove the logo, change its color, add custom links or menus etc etc. Now this tutorial explains you how in seconds you can turn your WordPress admin bar into a sticky footer bar without disturbing its symmetry and beauty.
You can customize WordPress admin bar. You can change its color, size and other style by adding some custom CSS. Generally this is done by adding a function to your theme’s function.php file. Second method includes editing siteroot-> wp-includes->css-> admin-bar.css file but I would not recommend you changing the core css files. As far I know there are no plugins available that allows you add custom color to wp admin bar. Here I am discussing another method which easily customizes your wp admin bar without disturbing anything on your site.