Create your own 3 column blogger template by adding a second sidebar to your blogspot blog, you can place the sidebar in any side of the blog.
By adding a second sidebar to blogger (blogspot) your blog will look more professional and you will have more space for your gadgets and widgets. Follow the bellow steps with attention , and first of all backup your template.

1. Go to your Blogger dashboard
2. Layout
3. Edit HTML
4. Find the sidebar-wrapper code, it looks like this:
#sidebar-wrapper { width: 220px; float: $endSide; word-wrap: break-word; /* fix
for long text breaking sidebar float in IE
*/ overflow: hidden; /* fix for
long non-text content breaking IE
sidebar float */}
5. Add the following code right after it:
#sidebar-wrapper2 { width: 220px; float: $endSide; word-wrap: break-word; /* fix
for long text breaking sidebar float in IE
*/ overflow: hidden; /* fix for
long non-text content breaking IE
sidebar float */}
So it will look like this: