Gray's is certainly the bible of such studies. A first edition would be a nice addition to your library

. I think most of the later versions are an attempt to make it more readable as the original was highly technical (how's your Latin?). If your set on Gray's I recomend reading the reviews for each, but there are many good 'anatomy for artists' books out there that will teach you all you need to know with some helpfull insights.
Dave