You can download the Sendcastle Email templates in a nice little zip-file. You can tweak them to your needs and then re-import them as your own templates in Sendcastle.
This can be useful if you want to change the width of a column, tweak some colours, add another editable section, or perhaps remove one -- well, the sky's the limit. You just need to have a basic understanding of HTML.
These templates are licensed under http://creativecommons.org/licenses/by-sa/3.0/
Click to download the Sendcastle Email Templates