Facebook Likes You! is simple plugin which makes it easy to add Like Button and widgetable Like Box. Google +1 isn't a problem too!
Try to uncheck 'Use XFBML' checkbox or/and register your own app ID. If it doesn't appear only in Internet Explorer, remove from your theme root
<html> element and put
<html xmlns="http://www.w3.org/1999/xhtml" xmlns:fb="https://www.facebook.com/2008/fbml">.
You can use simple BBCode
[fb-like-button] and place it by WordPress editor or – in another space (i.e. in your WordPress theme) – put
<?php echo do_shortcode('[fb-like-button]'); ?>.
Simply uncheck 'Use Open Graph' in settings. Extremely recommended if you've got another Open Graph plugin or put these meta tags on your own.