What spec are you? Are you min/maxing for raids? Or are you trying to make gold? More info helps.
But, maybe this could answer your questions:
WoWhead. I saw this linked in another thread asking about best professions for Paladins. Found it by using the search feature on this forum. It is nice ;)
Keep in mind it may be slightly outdated, I didn't read the whole thing, but it should give you a good idea.