I've seen so many people with their own "listing designer" and the ones available from eBay are so used and not something that to me grabs one's attention. I make my own html Free Templates to add as my "listing designer". Do I need software? If so what would it be? I'm pretty much clueless but am very eager to learn.
If you want to get a basic grounding in html, which is what you'll need to create listings templates or html emails, then there are a lot of good resources out there online.
A good place to start is with the beginner level HTML Dog tutorials.