Amazon for sure. That includes on-site and off-site SEO. Use it as an example. Think of the basics, good titles, lots of content, and tons and tons and tons of pages. Of course the url itself is so reputable that it filters down to everything else, but even without it, it's set up nicely.
For SEO-ing ecommerce website, first check the urls - if they are generating dynamic parameters appended to the urls, you need to prettify the urls to make them look like static urls, use appropriate SEO plugin for that, most ecommerce software like OScommerce have an appropriate Search engine frienldy plugin for rewriting urls, that would do. Further, use canonical form in your meta tags.
If you run an ecommerce site proper SEO is even more important than if you run a content site. Why you ask? Well you see ecommerce sites generally have lower traffic and higher income per visitor than a content site. What this means is that even a small increase in traffic can create a large increase in revenue. It is thus very cost effective for an ecommerce site to expend money on search engine optimization. For the most part an ecommerce site can optimize the same way as a content site, what with adding keywords and all of that. However there are some issues that, while they can exist on a content site, almost always exist on an ecommerce site. These issues are outlined below: 1. Search Engine-Friendly URLs It is extremely imperative that you setup your ecommerce site to use search engine-friendly URLs and if you can help it, meaningful identifiers. Most ecommerce sites are database driven and by default most shopping carts are not search engine friendly. This presents a very large problem because search engine may have trouble navigating to your product pages. Letting a search engine index your home page is not enough because people often search for exact products. For instance if you ran a golf store you would find that while some people do search for "golf clubs" they usually search for a specific brand or model club. To give you a more personal example, last year I saw a vase I wanted to buy for my mother in one of those generic "Gift" catalogues. I thought I might be able to find a better deal online though and so I searched for the 5 word product title on Google. I found a site that had both better deals and search engine-friendly URLs and I bought the product there. 2. Session IDs This goes along with search engine-friendly URLs but it is so important it deserves it's own section. Most shopping carts end up putting session IDs in the URL in order to track visitors, something that is required for shopping carts to function. You'd be much better off storing the information in cookies if you can so that if someone wants to link to one of your products they won't end up linking to a URL with a session ID in it. However that doesn't address the issue of search engines because even if you use cookies by default in most cases you'll still end up putting the ID in the URL for a search engine because search engines do not accept cookies. There are three ways you can handle this situation. One way is to detect search engines by accessing the HTTP_USER_AGENT variable and to turn tracking off for them. This is technically cloaking, however it is benign as you're using it to show the search engines what your visitors can see. Of course malicious cloaking is showing search engines something your visitors do not see.
WOW! Who need ebooks, just post your concerns here then write your own ebook. Just kidding. Your answers were all super rich in knowledge, insightful and well taken. The reason I asked was due to my first try at e-commerce. Thank God for tax write-offs. After 3 months I pulled the plug. I kept my merch/gateway accounts and planned on re-entering w/ a greater platform like Amazon. My research showed Amazon SEO and name recognition are bar-none in the marketplace (except eBay). Amazon's SEO is automatically placed in your e-commerce store and resolves all technical issues raised above yet very affordable as compared to the cost of other name brand SEO technology placed in your e-commerce store ($50K) upfront. That's just for the technology. Martin