<FORM  method="post">
<INPUT class="textbox" maxLength="20" size="20" name="ad">
<INPUT class="textbox" maxLength="20" size="20" name="ad">
<INPUT class="textbox" maxLength="20" size="20" name="ad">
<INPUT type="submit" onClick="window.open('gonder.php')" onclick="this.form.submit();this.disabled=true; return true;"  value="Gönder" />
</FORM>