Coda-plugins is a project mainly written in Python, it's free.
Plugins for Panic Coda Editor
Install – Copy the File CSS Box.codaplugin to User/Library/Application Support/Coda/Plug-Ins/ Restart Coda
HTML to CSS – Select your HTML Structure and get the CSS for the selected Id's and Classes.
CSS Beauty – CSS Reformatin
CSS Groundhound – CSS Reformating