Hi Steve, and welcome to SaleHoo.
Ebooks or any form of digital media downloading, such as MP3 files, are prohibited on ebay to the best of my knowledge. That being said, you can of course list hard copy products, so perhaps you could look at producing your guides in paper form for sale.
It actually sounds like quite an interesting product theme, and the fact that you are experienced in the field yourself gives you an opportunity to develop your own site where you could combine everything far more effectively than on ebay.
I'm not saying don't use ebay, could be a great place for you to start out, but with your experience, once you get some products behind you, then your own site would give you a seriously good opportunity to expand.