IE6 tweaking needed

Well, I see you've set the #newletter box to display: inline or inline-block. Why didn't you just float it right? (or did you have that earlier?)

Whenever I have strange spaces appearing, I start with debugging by adding ugly background colours to boxes. For you, this means the #newsletter box, the submit button, and various text... also the menu.

Your line-height is 10px so I don't think this is the case of IE6 trading line-height to height, but go ahead and check it.

There may be something invisible wrapping underneath; adding background colours helps spot this kind of thing (if that's the cause.

Last, and something to keep in mind if you're pounding your head over it: people tend to use just one browser (in general). So, that spacing doesn't look bad in IE6, and it's only noticeable because we've seen how the site looks in all the other browsers: typical web dev behaviour. However an IE6 user isn't going to ask you what that space is, unless they're using another browser to view it somewhere else.
Just something to think about if a bug like this is costing you too much time. Obviously, if you have a client who insists on it, you need to fix it.

Also, as a prolly unrelated note, my browser should never, ever be showing me this:

<link href="styles/muses_foot.css" rel="stylesheet" type="text/css" />
<?php
include('/home/muses/public_html/newsletter/embed.form.php');
?>
<script type="text/java

PHP includes should be HTML as far as the browser's concerned. They should never be able to appear in source like that.

Thanks for the colouring advise.
Made me find the culprit.
As per normal IE6 was not adjusting Margin changes in parent objects and so it was pushing everything down.
I added a IE6 specific style to do a -20px on the margin and all is fine now.

As for the pho include. Well it works like that. I took away the php tags and it appears as text on the website.
There is that old expression I guess. If it works don't try to fix it!

Thanks for the advise though.