Where to start with SEO. I would get a good book such as ‘the art of seo’ http://oreilly.com/catalog/9780596518875. This can be as time consuming and exhaustive as you want it to be. Basically, have unique page names and descriptions, if you are using a cms be careful of 301 and 302 redirects, do some research on the keywords you want to use - find one that is searched for but not currently uniquely offered, i.e. long tail searches. One word - content. If you have images all over the place - use alt tags or try the css image replacement techniques. Two of the most decisive factors that I have found are
1 - a well know domain name like cbs.com will give you leverage, so if you start as site at amazon.amazingfurniture.com you will be ahead of the game (although I don’t think this would be applicable to most small business sites).
2 - Links, links, links. Get well respected sites to link to your sites and in turn link back to them. The most fundamental principle of SEO is spiders following links and seeing whose linking to who. The rest is mostly trying to weed out the spammers.
I haven’t tried this yet but geographical info might be good depending on what you are trying to do. There are hundreds of variables in SEO depending on what your business model is and who you are marketing to. If you are a small business or startup and the internet is a large part of your sales model, I would design the site around SEO considerations and let everything else go second. Amazon doesn’t get any beauty awards but I go there almost every week, Google everyday. You don’t want a ton of hits, you want hits from people who will buy something. So if you are getting 10000 hits a day and a hundred sales and your site looks like something from an art museum, great, but if your site is bare bones, easy to navigate, you get 500 hits a day and 200 of those people buy something, which is better?
That’s my two cents :-)