Any Class Help What Are Common Build Items?

I have an abnormal amount of random legendaries sitting around my bank, and I've been trying to figure out whether they would be worth something to others.

Of all the randomly dropped items, what weapons/armors/accessories are most commonly used in builds of any kind?

(By "randomly dropped" I mean things that aren't obtainable from dungeon merchants, Hive, LI, etc.)

I also want to learn to make builds, so knowing which items are good will help me.

Thanks.