Spoonflower.com is a fabulous American site that prints your designs onto a range of quality fabrics like organic cottons and bamboo.
I had a shot at designing some fabric using an old vintage potholder for inspiration.
Another photo I took of an agapanthus blooming in the front yard morphed into this design. You can see your work in fabric form for as little as $5US for an 8x8 inch swatch.
Spoonflower can also put your fabric design up for sale on their site and you'll receive a 10% commission for your trouble!