so is there a way to customize Tagline for each page/post?

A blog has a tagline. A post doesn’t. What exactly is it that you want to do?

see where it says ‘medical coding and billing specialists’ in white in the header area of the post…
https://medicalcodingstaffing.com/2009/07/13/dental-assistant-2/san-franciscoca/506
I would like it to say the name of the post, in this case ‘dental assistant’ either instead of the ‘medical coding and billing specialists’ or Underneath it if its an easy fix…

You could try changing:

<div class="header">
<span class="top-title white block">
<a title="" href="<?php bloginfo('url')?>"><?php bloginfo('name'); ?></a>
</span>
<span class="slogan white block"/></span>
</div>

to

<div class="header">
<span class="top-title white block">
<?php if(is_single()):?> <a href="<?php bloginfo('url'):?>"><?php wp_title('',true);?></a>
<?php else :?><a href="<?php bloginfo('url'):?>"><?php bloginfo('name'); ?></a>
<?php endif;?>
</span>
<span class="slogan white block"/></span>
</div>

in header.php

this did not work as i cant find that in header.php this is what my header php looks like for now.
<link rel=”stylesheet” href=”<?php bloginfo(‘stylesheet_url’); ?>” type=”text/css” media=”screen” />
<link rel=”alternate” type=”application/rss+xml” title=”<?php bloginfo(‘name’); ?> RSS Feed” href=”<?php bloginfo(‘rss2_url’); ?>” />
<link rel=”pingback” href=”<?php bloginfo(‘pingback_url’); ?>” />

<title><?php if (is_category() || is_author()) {wp_title(‘:’,true,’right’);bloginfo(‘name’);}
elseif(is_tag()) {_e(‘Posts tagged with ‘);wp_title(”,true);if(wp_title(”,false)) {echo ‘ : ‘;} bloginfo(‘name’);}
elseif(is_404()) {bloginfo(‘name’);_e(‘ – Page not found!’);}
elseif (is_single()) {wp_title(‘:’,true,’right’);bloginfo(‘name’);}
else {bloginfo(‘name’);}?>
</title>
<?php wp_head(); ?>

anyone ?