I have been using an add-on called Auctionator to quickly find materials for my enchanting profession on the auction house. It provides a button on the enchanting skill window that allows me to automatically search the auction house for materials I can buy for a specific enchantment or item.
I have been leveling my enchanting profession by setting the enchanting skill filter to "has skill up" and using Auctionator to find the materials for the enchantment that provides the strongest skill up. This works well for me, but because of the varying price of materials it can be quite time consuming to work out the most cost efficient enchantment to use.
Is there a better way to find the best deal.