I just bought some at Disneyshopping.com They have a whole slew of new styles and some in their outlet section on sale. The outlet section at Disneyshopping.com is great because they have everything at a greatly reduced price! Sometimes they ARE out of certain sizes, but I have been lucky and I wear XL which seems to always sell out faster everywhere I shop! They are great. I got Mickey and Bambi and Tink and there's Eeyore and others too. (I did not see any Park specific tanks but only characters. I think if you want specific park tanks you will have to go through the DL or WDW delivears phone #. I am not sure of any store that carries the Park specific shirts, just characters.) On Disneyshopping.com, some of the tanks and cap sleeve shirts can be matched with matching shorts and long pants and zip-up jackets. The shorts and jackets and pants are a chenille type feel fabric and the shirts are cotton mix. You WILL find alot of them there! My delivery just got here yesterday! I LIVE in Tank tops and shorts, so I am always looking for Disney style ones. Go there and you will have them soon!
That was information about women's clothing, if you want men's try the Disneyshopping.com or some of the little shops around DL sell t-shirts and tanks although it is pretty seasonal specific. You will start to see more of the tanks and shorts as Spring and Summer get closer.