L.W.
P.,
Try www.olivekids.com. They have beautiful kids' bedding of the type you describe, and not too expensive. My son had the Trains, Planes & Trucks set which we originally got through the JCPenney catalog and I also saw at Target at one point; however, there is a much better selection of styles and accessories if you purchase from the website.
I found the website when looking for additional accessories to go with my son's set (quilt, airplane lamp, etc.) I was sorry to have to pack it all away when he outgrew it! They have added several great designs since then -- sports, rockets, wild animals and others -- lots to choose from.
Good luck!
L.