This will mostly come as you play the game. Crafting materials drop in the dunj, have the possibility to be given as a gift by the weapons, and can also be purchased in the stores in the town as well as from the merchant accessed via the vending machines within the dunj.
The materials include:
-Sugar
-Plastic
-Glass
-Glue
-Wire
-Fabric
-Steel
-Liquid
-Dark Essence
-Holy Energy