How to overwrite the add content page I created a content type "test", and I want to overwrite the add "test" content page (http://www.example.com/node/add/test); for example, I want to show something on the right part of the page. How can I do it?

the following is i want to do:

i used garland theme as my site's admin theme and my custommed theme company as my site's template. i created a content type named "hello" this content type is used for anonymous to submit content, the page's layout is (header, left, right, footer) some static content and the site navigation locate on the header. the left part is the form which is used by the anonymous to submit content. the right part will be put into some blocks which are generated by the views module. now the default create hello content page for the anonymous is garland theme's create content page. how to change the page shows like the above layout as what i said. thank you.
Maybe implement hook_theme() in your template.php and add an extra template for the test_node_form:

return array('test_node_form' =&gt; 
    array('arguments' =&gt; 
        array('form' =&gt; NULL), 'template' =&gt; 'test-node-edit'
    )
);


Now you can write a test-node-edit.tpl.php for the form. But that's only for the form, not the whole page.