I see a lot of great Rare items on the Auction house (very high damage weapons with socket, CD, etc.), jewelry with all the things you look for, etc.

Question is, where do you find the best rare items? Can they be found in any act? Or do you need to play in the final act to find them? Or do they come from crafting? If so, which item types should be crafted? (I notice some crafted items say account bound).

Thanks in advance for any help.