Need some blog help!!

I'm in need of some blog help, because well, I'm a bit technologically challenged.

First of all, I'm trying to figure out how in the world I can make my blog 3 columns. I tried googling to find some layouts, but haven't the slightest idea of how to "install" them on my blog.

Secondly, I want to make a "button" for my blog so that readers can add it to theirs. I was told I could make my own, but again, haven't the slightest on where to start.

If anyone has the time & smarts to help me out, please contact me . I would much appreciate it!!!!!