Today I spent time to convert my blog from the default 2 column to 3 column layout. I wanted to do that because the side-bar (on the right) was getting too cluttered with information.
First 10 minutes on google lead me to this link here, which provided simple instructions to modify the default blogger template to do what I wanted. Since I had earlier modified the template (to fit the top-navigation-bar) the instructions did not apply as it is, but the explanation provided was useful and I managed to complete this in 15 minutes. Thanks Mr Hans.