Web site design & search engine optimisation

We are a Claims Management Company and are looking for someone to design a website for us with website and search engine optimisation using organic methods. Search engine optimisation is very important to us as we shall be receiving future clients via the website and therefore the website should visible on the first page of search engines such as google on a continuous basis. The size of the website should be approximately 40 pages bearing in mind the information that it needs to contain and will also need to contain interactivity forms such as enquiry forms and call back forms.
The website needs to be in a format where it can be updated on a regular basis. We do not require a domain name as we already own this.
NO TIME WASTERS PLEASE ONLY PEOPLE WHO CAN DO A GENUINE JOB.