Welcome to TTF!

The easiest way is to submit the form to target="_blank" - here's some sample code in HTML/PHP. The PHP code is just so the form doesn't get displayed:

[PHP]<?
if(isset($_POST['something'])) {
echo $_POST['something'];
}
else {
echo '
<form action="'.$_POST['SCRIPT_NAME'].'" method="post" target="_blank" >
Input Something: <input type="text" name="something">
<input type="submit" value="Submit">
</form>';
}
?> [/PHP]

Any questions, just ask.