I’m continuing to learn as much piece meal or trial & error as in an organized read the manual manner. After fiddling around with the last theme until I liked it I read an article Chris Price at A3Webtech wrote. He said, “The simplest way to check a basic level of quality, as ever, is to go to the W3C online validator at http://validator.w3.org and check the website’s index page.”
Regarding your site showing up on search engines: keeping it fresh – fresh new information. One way to do that would to have a blog. Although it can be a separate stand alone blog, it might also be an information page that you update regularly.