I agree with tvrlover, he definitely knows what he's talking about. It really is just the tip of the iceberg, not hard but you have lots of work ahead of you which starts with research before you jump in.
I would like to suggest www.instantestore.com for you to check out. They offer a 30 day FREE trial so I think you should give it go and see how easy it is to set-up and manage your own ecommerce store. This company has been around, has excellent customer service and their website is very user friendly. No contract, low cost and includes hosting. They include SEO (search engine optimization) tools. Many professional-looking templates to choose from, if you don't like any of them, they have reasonable rates for custom design. I have used them for a variety of things. When you become advanced enough, you will be able to easily figure out how to incorporate a blog. Write product reviews on stuff you're selling is a good start.
I agree with Knowitall, yahoo is highly recommended. I've used yahoo for so many things. I just registered another .com domain with them for US$2.99. If you're planning to sell your products in US dollars, I would suggest going with .com, if you're planning to sell in HKD, then go with a localized domain. I know that when I'm looking to buy online in Canadian dollars, not US dollars, I type in the .ca domain.
You will quickly see how low the entry barrier is to becoming an etailer so find a niche market, minimize your start-up costs, get the website up & running quickly (don't waste time on getting it fancy!) and follow tvrlover's suggestions... good advice that's free is hard to find. I have spent many, many hours surfin the web thru google and still do! Current library books on the subject help too.
Good luck and best wishes!