So you want a picture appended to your blog title and/or blog description. No sweat.
I have found that it is possible to put HTML tags in the post title which means that you just have to add a <img> tag
Sign into Blogger (Dashboard > Settings > Basic > At the top will be the boxes (fields) for typing in the blog title and blog description.
Thus if you want an image followed by the post title, you will then type into the field for the post title the following:
<img src="picture url" /> "put the post title here without the quotes" replacing "picture url" with the actual picture url and "post title" with the actual post title. Below a screenshot to illustrate: