This plugin adds up to four new buttons / links to the WordPress Editor panel. You can select to add a quicktag to easily insert: 
Amazon item links 
Amazon product searches 
custom span class 
custom div class
The settings pane allows you to enter defaults, as well as your own Amazon associate ID.

David’s Ultra Quicktags

Adds new buttons to the Editor window (Amazon Links, Amazon Search, etc.).

<ul>
<li>Author: <a href="http://san40us-blog.ru/about/" rel="nofollow ugc">San40us</a></li>
<li>Website: <a href="http://san40us-blog.ru/" rel="nofollow ugc">http://san40us-blog.ru/</a></li>
<li>License: GPL v.2 see the bottom of</li>
</ul>
Lightweight and easy to use plug-in for easy text formatting while writing a comment. It has the ability to create custom tags and buttons. Automatically built into the shape of the element to add comments textarea, immediately after activation. In most cases, your hand does not need to install the hook into the file comments.php.
<h3>License</h3>
<pre><code>
</code></pre>

Comment Form Toolbar

Plugin for quick formatting comments with html-tags

David’s Ultra Quicktags vs Comment Form Toolbar