I cannot believe i am having this much trouble.
All i want to do is add a simple textbox to the sidebar  using a text widget like

<div align=center>
<form name="signup" id="signup" action="thankyou.php" method="post">
<label for="e-mail">Enter E-mail Address</label><br /> <input type="text" id="email" size="35"><br />
<input type="submit" value="Submit" />
</form></div>

When user clicks submit i just want to add the email to a mysql table. This seems like a simple thing but cannot get it to work. On the thankyou page i am using

<?php
mysql_connect ('localhost','username','password');
mysql_select_db('dbname');
$data = $_POST['email'];
$sql = "insert into 'wp_email' ('email') values ('$data')";

mysql_query($sql);

echo $data;
?>