You're welcome, check out these locations
See what people are looking for. What keywords they're using to find products. What they're spending money on and what makes them spend money. Go for a niche where people constantly buy new products. You don't wanna go into niche where people buy one product and that's pretty much it.
Try to go through forums aswell. Type in Google:
"niche+forums" or "niche+discussion board" (replace niche with your keyword/desired niche)
On these forums you will find valuable information about your prospects. Check out the FAQ and you'll have lots ideas too.
Also check out your competition with a tool like Market Samurai:
You don't wanna go into a niche with large companies sitting there for years at the top.
You now got a load of valuable information some people would charge you for:) Take it easy and have a good action plan or else you will suffer from information overload