Adding code blocks to blogger

To put a “code” block in any of your blogger blog posts, you have to first modify your template a bit.
1. Login to your blogger account
2. Go to Layout > Edit HTML
3. Find ]]></b:skin>
and just ABOVE it, add this line of code:
code {background:#EEEEEE; font-family: Trebuchet MS; display:block; border:1px solid #999999; padding:10px;}


source: http://atoz2u.blogspot.com/2011/03/how-to-add-code-and-blockquote-blocks.html