antocara

Add a box with information about the author of each post after post written by that author. 
This box will display information in bio of each writer’s blog, a link to every post written by this author, avatar, and a series of icons link to author profile on social networks 
are known as Facebooks, Twitter, Google+ and icon for contact by email.
All these data the author of this post are collected from the profile of each author which have incorporated the necessary fields to fill. 
Author Info also has a widget in which appear a list of all components of the blog who have permission to write to the blog. This widget also displays the avatar of the author, 
his name with a link to a list of all posts written by him, the same icons to link to your profile on social networks and the number of written post. 
The box appears with the author’s information after each post is configurableboth in its background color, the color of the lettering and decorative border color of the table below.
Author info is configured for use in multi mode to be available in:
<ul>
<li>Spanish </li>
<li>English</li>
<li>Italian (gracias @cento)</li>
</ul>

CW Author Info

Add a box with information about the author of each post after post, include a widget in which appear a list of all components of the blog

David Shabtai

glanum

<ul>
<li>NEW each author now links to a personnal page or external URL, in addition to author posts (default)</li>
<li>NEW better integration with home, archive categories and custom loops</li>
<li>NEW a few more options with avatar, before/after content</li>
<li>NEW no repetition of author name if revision author is the same</li>
</ul>
This great simple plugin, written with <a href="http://www.glanum.com" rel="nofollow ugc">multimedia agency</a> Glanum, adds the author and date at the top or bottom of the content on posts, on pages and on archive categories (optionally along with last modified date and author), with a fully custom per-post / per-page hide option. Especially usefull for multi-author sites and blogs:
<ul>
<li>Name of the author of the post or page, optional avatar</li>
<li>Date of first publication</li>
<li>Author and date of last revision</li>
</ul>
It is flexible and offers the following options in the admin menu:
<ul>
<li>Display the post author info independently on posts, pages, archive categories and home</li>
<li>Specific per-post/per-page exception: hide the info on any post and page you want!</li>
<li>Choose: before or after the content or the excerpt independently</li>
<li>Optional link on author name to WP’s default author posts list or now to a custom author page or external URL</li>
<li>Write your own label before and after the name of the author: e.g. <code>Contributed by</code> Author Name <code>for OurNewsBlog</code></li>
<li>Date of 1st publication is optional, and supports surrounding text like above</li>
<li>Author and date of last revision are both independently optional, and only display if revision author or date are different from the original, with surrounding text</li>
</ul>
The plugin is initially intended for very small to much larger multi-author blogs (newspaper, magazine, webzine, collaborative publications, communities…) when an article is supposed to be signed by its author and not remain anonymous, as commonly expected in journalism and publishing.
<ul>
<li>Lastly, information is displayed in nested <code>div</code> and <code>span</code> so it is CSS ready, just up to you to do the styling to your taste. See the screenshots.</li>
<li>Integrates great with qTranslate for multilingual or international blogs, using <a href="http://www.qianqin.de/qtranslate/forum/viewtopic.php?f=3&t=3&p=15#p15" rel="nofollow ugc">Quicktags</a></li>
<li>Available in English, French, Belarusian (credit <a href="http://pc.de/" rel="nofollow ugc">Marcis Gasuns</a>), German (credit <a href="http://diensten.kiwa.nl/mvo" rel="nofollow ugc">Rian Kremer</a>), Hebrew (credit <a href="http://www.sagive.co.il" rel="nofollow ugc">Sagive</a>), Romanian (credit Luke Tyler), Slovak (credit <a href="http://webhostinggeeks.com/user-reviews/" rel="nofollow ugc">Branco Radenovich</a>) and Farsi (credit <a href="http://www.itstar.ir" rel="nofollow ugc">Hamed Nourhani</a>).</li>
</ul>

Post Author

Display author, writing and editing date - fully customizable for content, excerpt, home, archive... with exceptions. Great for multi-author websites.

CW Author Info vs Post Author