Hmm, in that case...well, I'm not all too sure. HTML is static information which is displayed directly on the client's side, as is JavaScript (client-side)...to be able to send it to yourself in an email would require a mail server, (well, I've never done it with anything but PHP and a server with mail included), but Geocities doesn't...
If you had a friend with a PHP-enabled server, you could have them host a simple script for you, that would do that... I'm not entirely sure of all the ways to do this, as I never really got into Javascript that much...
One way (there are surely others, maybe easier too?) is...
just have a small popup window that goes to a file hosted by a friend,
script.php
<?php
$emailto="youremail@address.net";
$subject="the subject of the email";
$ip=$REMOTE_ADDR;
mail($emailto, $subject, $ip ?>
and then use javascript to close it. There are all sorts of scripts to hide the window in the background (and it'd be so quick (generally) that most would not notice). But doing it with simple HTML/Javascript is not possible... :-/