Where do I paste my Yedda profile code in Blogger's template to add it as a widget?

Did you switch to the blogger beta or are you using the classic blogger? 

If you switched to the blogger beta, it's very easy:

1. Go into the dashboard
2. Select the "Template" tab
3. Select the "Page Elements" sub-tab
   
4. Click the "Add a Page Element" link. A new window will open.
5. From the list, choose "HTML/JavaScript" and click "ADD TO BLOG". A new window will open.
   
6. Type in a title (anything will work - e.g. "My profile on Yedda")
7. In the Content area, paste the widget code from Yedda
8. Click "Save Changes", and that's it.
   

You can move the widget position around in your blog sidebar by dragging it.

You can put it anywhere in the template's HTML code but the most suitable place is the sidebar.

Go to the your blog's dashboard and edit the template.

Now, look for something that says <!-- Begin #sidebar --> . Followed by <div id="sidebar"><div id="sidebar2">. If you put the code you got from Yedda after these two <div>'s , it will show up on top of your side bar. If you put it further down below at the bottom of the sidebar (just before </div></div> <!-- End #sidebar --> ) - it will show below your current sidebar. 

 Just play around with it and use the "preview" button in blogger to get the desired result.