If you already have a website and instead of customer queries you receive in your email box only spam, it is time to think about optimizing your website (Besides, it was better to secure the web form against the spambots.)
Use your favorite Internet search engine (google, bing, yahoo, ask.com, or whatever you use), and search the words by which you think your customers find your services. If you are on the first page to the fourth place, you did a lot of work have to optimize your site. If you are not on the first or second page of results, your website does exist, but the most benefir from it has your webhosting company that you pay a fee for hosting your website. In such a situation, your website brings minimum profit and has to be optimized.
If your website was properly designed and developed according to the web standard, contents analysis is required and changes to be done to the contents to be readable both for your customers and search engines that will increase the page position in the search results. If your web pages were not properly designed and developed, it is necessary to modify the source code to bring it up to the web standards and optimize.
It is advisable to incorporate optimization into the web design for newly created websites. Although it makes web design and development time a bit longer it ultimately is reflected in the increased quality of the websites and in higher position in search engines results.