PHP MySQL Developer

Hi We have an ongoing requirement for a PHP programmer, at least 20 hours a week, probably more initially. We are looking for an individual, not a team. If you can "do" website design then that's a bonus. Obviously we are looking for somebody who will do good work for a fair price. The first project is to provide a user tracking module that records when a user enters one of our sites, follows their progress through, and ultimately records the value of their sale if they make one. The code will record the referrer details for further analysis. We will provide the database schema and the design requirements.