[eSekar]

you will have to edit the contactus template from your Admin CP, you'll find your way in that template to add any text you want,
for example you may add your text block in a DIV tags below the following:

PHP Code:

<div id="pagetitle">
    <h1>{vb:rawphrase contact_us}</h1>
</div> 


This will make your text right below the page title in the page.

Good Luck.