write a professional ebook about a popular niche market and upload it in onto my website.

Hi, I have my website built but I do not have a product of my own to sell, I was wanting to find a popular niche market and have someone write an ebook that I can sell from my website. Popular niche markets are, Making money online, Stock Market, Hair loss,Weight Loss, How to win Lotto, Best odds of gambling, Video games, There are so many niche markets that have not been discovered yet, I was wanting some ideas about a good niche market I can start and was wanting someone to write an ebook about that niche.