t shirt designers

I am looking for a talented designer to create 4 to 7 custom t-shirt designs with a cartoon/illustrative and specific theme. The theme I have in mind will be provided to the chosen designer, as well as any guidelines about what I'm looking for. I need the t-shirt designs to be delivered in a file format that can easily be printed and shipped. Additionally, they should look great online or in print form and be eye-catching. The overall style should be professional, yet playful.