buyza on "Help with mapping readers"

I found an old topic of this, but it only gave me limited help!

I'd like to be able to see where my readers are coming from (Like google analytics) and found here that you can use something like whosamungus and flagcounter (http://en.forums.wordpress.com/topic/traffic-location-hits?replies=3#post-316012) but I don't know how/where to load it to my blog. Do I have to post the code on each post?

Or is there a way to post it in generally to the blog somewhere. Thanks!

Kirsten