Keevee,
I noticed no one answered you on this so I'll chime in and tell you what my experience was with Astores. I built a bunch of them a couple of years ago and did exactly what you asked about. I built a lot of back links to them and my search engine listings were good for awhile but dropped way off after a few weeks. They didn't have any staying power so I changed my strategy.
I decided to build Amazon stores from the paid version of the AOM script. I built 7 niche stores and built a ton of back links to them. They not only have staying power but they stay high in the listings and make me money every day. They are also perfect for running cheap clicks on the Google content network.
A lot of people moan and groan about Amazon not paying that much in commission. What they forget is people buy a ton of stuff on Amazon because they are trusted and have great prices. Perfect for this economy, in fact, my Amazon stores are absolutely cranking right now.
You may want to consider building one store with the free version of the script just to try it out. You can always switch it to the paid version if you like it. Then start building some back links. Hope that at least gives you one idea of what you can do with Amazon. There really is endless possibilities with Amazon.
EZ