If you are comfortable with some code editing in your self-hosted WordPress installation then TheNextWeb & Alex Moss, have a nice hack for you.
Add a Google+ share button to your WordPress blog with this plugin
GoogleCards is a simple WordPress plugin that will add a generously sized Google Card to your widget area.
If you don’t use widgets then there is a PHP snippet which you can add to any part of your WordPress template.
Developed By John Henson
WordPress plugin for Google +1 button. This plugin displays the google +1 button in different styles and positions.
This widget displays image links (icon buttons) to various subscription services and social networking sites.
Up to 30 services supported now including Google+
Developed By Srini G
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