jackyfox

VKontakte Share Button plugin brings powerful way to add VKontakte share button for you posts and pages.
It supports all functions of VKontakte API and easy customizable:
<ul>
<li>You can choose one of seven button appearance types include custom</li>
<li>Place button on posts, pages and frontpage at will</li>
<li>Select location of button: before or after content, on the left or right</li>
<li>Exclude pages and posts by ID which should stay without buttons</li>
<li>Choose description of content: forepart of post/page or global description for all site</li>
<li>Can be used description from meta tag <code>description</code></li>
<li>Use your own site logo image specifying link or with meta tag <code>image-src</code></li>
</ul>
You can use the shortcode <code>[vk-share-button]</code>.
Also can be used PHP code in your template:
<pre><code><?php if (class_exists('VKShareButton'))
 if(!isset($VKShareButton)
 $VKShareButton = new VKShareButton();
 echo $VKShareButton->the_button() ?>
</code></pre>

VKontakte Share Button

Plugin allows you to add fully customizable share button of VKontakte social network.

igrp

VK Lock make is possible to restrict page\post access to authorized VKontakte group members only. 
Plugin will take care about site visitor authorization in VKontakte and checking if he\she is member of VKontakte group specified by you. 
Access to the protected page\post content will be allowed only if user is authorized and is a group member.
Restriction works for password protected pages\posts only – this means that your have to set page\post type to “password protected” and specify any password (plugin does not use this password, if you like you can access protected page with that password via conditional password access form, provided by WordPress).
Plugin works via VKontakte API (https://oauth.vk.com/authorize) therefore you need to make some proper (its very easy) settings at VK.COM side. See Installation instructions.
This plugin may not work properly with PHP versions earlier than PHP 5.2

VK Lock

Restrict page\post access to authorized VKontakte group members only.

VKontakte Share Button vs VK Lock