I've heard some people saw results with Carlson's, which is pretty widely available...  but I really can only recommend a high-quality fermented one like the Green Pasture's.  It has to do with the processing destroying the vital nutrients (which are what helps your skin). Also the ratio of vitamin D to vitamin A.

Just did a post on this yesterday so check it out for more info:
http://beautyeditor.ca/2010/09/02/the-single-best-product-evah-for-your-skin-is-not-in-fact-an-actual-skincare-product/