Thank you gillie!

You're a great teacher. So, I'll be busy from now to study and learn that things.

Respect!

Take a look at this xini757 : http://blog.arvixe.com/how-to-change-the-color-of-the-top-bar-menu-in-elgg-1-8/

If you down in this article you can also change the header - I am also new and was able to change this with the information

Thank you Piet Muller!

your information was very usefull!

Respect!

Would it be wrong to replace elgg_toolbar_logo.gif and favicon.ico  in the _graphics folder to

something else of the same size with the same names.  

You should add a new logo and favicon to the graphics folder in your own plugin. And then use something like below. Read the thread mentioned abowe and you'll find solutions to both changes.

elgg_unregister_menu_item('topbar', 'elgg_logo');

$logo_url = elgg_get_site_url() . "mod/myplugin/graphics/topbar_logo.png";
elgg_register_menu_item('topbar', array(
    'name' => 'my_logo',
    'href' => 'http://www.mysite.com/',
    'text' => "<img src=\"$logo_url\" alt=\"My logo\" width=\"38\" height=\"20\" />",
    'priority' => 1,
    'link_class' => 'elgg-topbar-logo',
));

Old thread but here is the noElgg Logo plugin:http://weborganizm.org/file/download/1166/nologo-zip