This post helps you to add Google Buzz button to your blogger blogs.
Follow the instructions given below:

Please Note: Before Editing your Template, Save a copy of your current template by clicking ‘Download Full Template’ in ‘Edit HTML’ page of the Blogger ‘Layout’ Window and ‘Preview’ the changes before Saving.
  1. Go to Blogger Layout page – Edit HTML – and click Expand Widget Templates.
    How to Add Social Bookmark Links beneath Blog Posts in Blogger
  2. Search (Ctrl+F) for:
    <data:post.body/>

    and REPLACE the above line with the following code:

    <!–GOOGLE-BUZZ-BUTTON START–>
    <a title=”Post on Google Buzz” class=”google-buzz-button” href=”http://www.google.com/buzz/post” data-button-style=”small-count”></a>
    <script type=”text/javascript” src=”http://www.google.com/buzz/api/button.js”></script>
    <!–GOOGLE-BUZZ-BUTTON END–>
    <div style=’clear: both;’/>
    <data:post.body/>
  3. Now Save your template

Happy Buzzing!