example templates and documentation for use

All the information I’ve found to use custom templates for comment display are of no help. They only go as far as explaining how to specify what template to use.
http://wiki.modxcms.com/index.php/Jot

&tplForm=`comment_form` &tplComments=`comment_tpl`

What is the syntax to access the comment variables in the templates? [*createdon*]?

What are the available variables that can be used in the templates?

Where and how should I have found this information on my own without having to post in the forums?

Jot templates all contains heavy usage of PHx: http://wiki.modxcms.com/index.php/PHx (PHx is part of Jot)
You’ll find the default templates and css in the Jot folder. Copy this code to custom chunk "tpl’s"
and start "playing". You can use tv’s [*...*] and snippets [[...]]
as usual though it takes place in the current document. A Ditto chunk tpl is different and presents
information from a chosen document.