Need help accessing $wpdb

I’ve got a simple problem, but can’t find the syntax to make it work. I put some conditional code in page.php to force a registration page when a user goes to a page without having first logged in, and it works fine.

<?php
if ($thePostID == 2700) {
 global $current_user;
 get_currentuserinfo();
 $user_id = $current_user->ID;
 if ($user_id == 0) include("register.form.php");
}
?>

Here’s the register.form.php:
<form name=”registration” method=”post” action=”/wp-content/themes/kbb8/register.form.post.php” >
<p><label for=”BQ_name”>Name</label><input type=”text” id=”BQ_name” /></p>
<p><label for=”BQ_email”>E-mail</label> <input type=”text” id=”BQ_email” /></p>
<div style=”padding-top:4px;” >
<input type=”button” name=”button” value=”Submit”>
</div>
</form>

Here's the action code:

<?php
echo “I was clicked!”;
echo “<p>”;

$grf_name = $_POST[‘BQ_name’];
$grf_email = $_POST[‘BQ_email’];

$sql = “insert into wp_gRF (gRF_name,gRF_email,gRF_date)
values (‘$grf_name’,’$grf_email’,NOW())”;

echo $sql;

global $wpdb;
$wpdb->query($sql);

echo “<p>”;

echo “Your registration has been submitted!”;
?>
`

When the button is clicked, the “I was clicked” and the sql statement echo, but then I get the following error: Fatal error: Call to a member function query() on a non-object in /home2/kidsknow/public_html/wp-content/themes/kbb8/welcome.skip.php on line 20

What am I missing. I know this is basic, but I just haven’t been able to get ahold of the syntax to make this work.

THANKS!!!