[nightstrike2]

I'm getting the hang of writing these addons, but now I'm going to embark on a new path of trying to modify the item tooltips that pop up. Right now, I run with CraftStore (Rhyno's version), MM, and Master Recipe List, all of which modify these tooltips. It's very difficult to extract from their code bases, however, how to do this simply.

What I'd like to do specifically is modify the tooltips of achievement furnishings. Before you get the achievement, the tooltip text tells you in red what you need to do to be able to purchase it. After you get the achievement, the text is gone. I'd like to make an addon that, after you get the achievement, puts text in there (maybe in green) telling you what you did to be able to buy it.

Can I get some pointers on how to start this?