Automating Simple Mail Text Replacement

I have never wrapped my mind around Applescript. What I'm trying to do is this. Given an open Apple Mail message, take the selected text and do something with it. So, for example, the message reads:

-----------
Hey! Check out this link:

-----------
and the 12345 is selected. I want to have that replaced with:

-----------
Hey! Check out this link:

-----------

(I've substituted curly brackets for square ones so as not to confuse the forum software overly.) I'd love to do this in Ruby, which is second nature, but I don't know of a way to invoke that from the Mail menu. So much for open scripting. Hence my question, how the heck does one write Applescript and navigate the object model?

Thanks

Hi cwd1,

While I can't answer your question directly nor am I sure I fully comprehend what you are asking in the first place, I thought you might appreciate the following:

Unlock More of Your Mac’s Power!