Experienced Graphic Designer/Illustrator for T-shirt Company

We require someone that has EXPERIENCE creating designs for T-Shirts. We are looking for someone to become a permanent member of staff, but will need to assess their work over a 3-6 month period before accepting them on a longer contract. Initially we will be looking to get them to do a number of designs based on concepts that we choose and if we are satisfied with the work we will increase the work load accordingly. No time wasters please! Specific experience designing T-shirts is an absolute requirement.