Instances/Copies

Hi guys, I think I have a very easy question to answer but I am stumped.

I have nice little buttons with images on my flash page, and I want to make a bunch of them but only change the base image, I’m getting a little tired of creating new layers and actionscript for each one, but everytime I copy and paste it, any changes made to the new one’s image also changes the first one’s image.

How do I copy and paste a symbol and have it free to edit?