Blizzard did it again! They updated their Armory page with a new item search! You can now select a search for items in the item drop down menu. You can also click on dungeons to see what their loot is. Also, you can look yourself up and you can mouse over your gear and see what upgrades might help you with that gear slot.
To do that, just mouse over the arrow near your slotted item and it will have a link that suggests an upgrade. The arrow is kinda hard to see. I tried my gloves and the arrow was a thin bar on the right hand side of the box that houses my gloves.