I, and several other guildies, use AtlasLoot for an in-game mod to do that. 

Outside of game, there isn't anything that does exactly what you ask, that I know of, but there are several loot tables out there; I like to use [url]http://69.41.171.43/[/url] but I'm not sure how updated it is. And with that one you have to go to the instance and such and such.