To earn well with e commerce sites just set up a quality site around that topic which you like and most searched for through out the internet, then leave an affiliate link in your site which will earn you money. To find low competition and high search volume keywords use Micro Niche Finder software.
I think that you need to think of things that interests you most. Think of a product first before constructing your website. In that case you can come up with unique and interesting ideas that can generate and fill in your site. for example if your inclined to music, then why not think of a music website.... if you are into cooking, why not start with recipes and stuff.. Something interesting is something worth visiting. Also think of viewer's interests.
Sites like amazon and ebay. Basically any site that sells items that the common man might be interested in buying at a bargain price without having to make a trip to the local mall.
Hi well, I required your suggestion kindly answer my query... I have plan to start online shopping site (But particularly one Dress product) Whether Shall I try with new site or participate amazon and ebay??? I have well SEO background...but have little fear to start .... if you have any idea please share.. Advanced Thanks