the best catagories are forex, weight loss and affiliate marketing ebooks, but these are also the hardest to make money with, its better to leave thoughs topics to the people with more experience, what you need to do is work out what sort of topic you are interested, if you like golf or surfing then i suggest you try and sell ebooks through Clickbank. in a bit of a hurry at the mo but email me at leisuretimebooks@hotmail.co.uk and we can discuss exactly what you want and i will help you.