After you have that great looking site that has been SEOed, you'll want to see where your site is coming up on Google (it usually takes about 2 weeks before a new site is indexed). Then to raise your rankings (or hold on to what you have if you're happy), you'll want to do some ongoing on-site SEO, and some off-site SEO.
Additional on-site SEO would be blogging on a regular basis, on your own blog that is hosted on your domain. It could also be adding content and or pages to your site on a regular basis. The more you add, the more Google will visit your site, and the more keywords you will rank for. You will rank higher, and for more words, so keep it up on a regular basis.
Off-site SEO is comprised of things like getting links from other sites, and blog commenting on other sites and linking back to your site from your posts, social bookmarking, article ssubmission, directory submission, etc. Do not minimize the importance of these things, as in today's Internet they are more important than you may imagine.
If this is starting to sound like a lot of work, you'll want to consider the benefits. Remember that the first result on Google gets 42% of the hits, and that the results on page 3 get almost zero. A few hours per week can mean the difference between having all the business you want, and not having enough. It's often worth it to pay someone to handle your SEO and link building.
Other ways to promote your brick and mortar business are through social media marketing, which is another form of off-site SEO. That's outside the scope of this article, but I plan to go into that at a future time.