Need to Add a Graphic Artist to our Staff - Ongoing

We need a person to add to our team who can do inexpensive drawings on an as needed basis. When drawings are needed, the selected graphic artist will be paid on an hourly basis. Most designs will be very simple and should not even take an hour, but we will pay the hour minimum. An example of a drawing that is needed now is the picture on this page showing the air flow through a house: [login to view URL] We need something like this ASAP showing the airflow through a single story house. When assignments are given we need someone who has quick turnaround, like within 1-2 hours. Some weeks you may have no assignments, some weeks you may have a lot. Please attached samples of your drawing skills.