http://wow.allakhazam.com/db/skill.html?line=165
Has a list of the tribal, elemental, and DS stuff. As for which one to do and what the price is. That can vary greatly depending on the server. Im on Staghelm and none of the stuff seems to sell very well. Im at 290 in LW and havnet picked a specialty yet since the market seems flooded w/ hunters and hi lvl LWers. I see the same few folks peddling the same stuff. I myself have looked into dragonscale since I could use some of the items myself. Ive seen the bp as low as 45 gold over the last few weeks. Id suggest looking at the list and keeping an eye on the AH and trade channels to see what folks want.