This is a great site for Tee shirts for Agility, Obedience, Rally. They have just about everything for all sports. I have gotten quite a few shirts from them. Two of my favorites one that says My dog has two speeds Fast and Faster, and a sheltie one that says Welcome To The Bark side. www.beautyofthebeasts.com
Those are awesome shirts. I love the 'Praise the dog, slap the handler' one. I may need that when we start agility 
