I hate saying this... but just do all the quests. lol Pretty much every quest that has gear rewards has one from each "armor class." Leather, cloth, plate, and mail. Not only that, but pretty much half of the mail gear offered is for Resto/Elemental shamans.
Also, a LOT of the quest gear is fairly comparable. There are some items that are definitely upgrades, but a lot of it is kind of parallel gear (lose crit for more attack, lose stam for MP/5, etc.). I also think there's a gear guide in the FAQ sticky that links you to a list of 60+ gear and how to obtain it (instances, quests, etc.)