You may decide that you don’t have time to optimize your site and would prefer to hire an Search Engine Optimization (SEO) expert. One important thing to note is that the best SEO expert’s websites don’t always show up first in the search rankings. Sometimes SEO experts who show up top in the rankings have clients who don’t. The reason for this is that a really good SEO expert may be too busy to keep his website in the top of rankings, because he is busy getting and keeping his customer’s websites in the top of the rankings. When you choose an SEO expert make sure that they can show you that their client websites are getting good traffic from their work and that their clients are happy with them. Ask them if you can contact their clients for references. If they give you the run around, then YOU should run… run to find someone else. Google® has some good recommendations for what to look for when hiring an SEO expert, so I suggest you look at their information: http://www.google.com/webmasters/seo.html
The general idea is that if it sounds too good to be true, it probably is.
You may also want to look at hiring Website Promotion or Search Engine Marketing expert as opposed to a strictly Search Engine Optimization expert. It is best to get traffic from a variety of sources and not rely totally on the Search Engines. Search Engine Marketers and Web Promotion experts focus on the whole picture and not just the SEO.