No problem! Those are all a medium, and my waist is 29, bust 34. I just took a wild guess and ordered a medium for my first shirt, and that fit so I got a bunch more. I didn't notice Gaia had sizing information until I had already ordered:
http://www.gaiaonline.com/store/gaiamerchandise/gaia_store.php?mode=sizingBut yeah I love the length of the shirts, because most women's pants nowadays are becoming "ultra-super-amazingly-omfgyoucanalmostseehercrotch-low-rise", so I prefer a shirt that can cover the area that these dang new pants show.