Select the buttons and style you want on a site like www.addthis.com and copy sharing the code.
Use Q2A advanced theme editing (see more on that here: http://www.question2answer.org/themes.php#advanced ) to override the q_view_main function and paste the AddThis code to produce something like this:
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function q_view_main($q_view)
{
$this->output('<DIV CLASS="qa-q-view-main">');
$this->output('
<!-- AddThis Button BEGIN -->
<div class="addthis_toolbox addthis_default_style ">
<a class="addthis_button_facebook_like" fb:like:layout="button_count"></a>
<a class="addthis_button_tweet"></a>
</div>
<script type="text/javascript">var addthis_config = {"data_track_clickback":true};</script>
<script type="text/javascript" src="http://s7.addthis.com/js/250/addthis_widget.js#pubid=ra-4d971b0a058477f1"></script>
<!-- AddThis Button END -->
');
$this->q_view_content($q_view);
$this->q_view_follows($q_view);
$this->post_tags($q_view, 'qa-q-view');
$this->post_avatar($q_view, 'qa-q-view');
$this->post_meta($q_view, 'qa-q-view');
$this->q_view_buttons($q_view);
$this->c_list(@$q_view['c_list'], 'qa-q-view');
$this->form(@$q_view['a_form']);
$this->c_list(@$q_view['a_form']['c_list'], 'qa-a-item');
$this->form(@$q_view['c_form']);
$this->output('</DIV> <!-- END qa-q-view-main -->');
}
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