I went out and got a couple of them. To get them I suggest you get more than 20 full pitchers of water and then you find a water elemental and double click the full pitcher of water and target the water elemental. Try not to kill them. I didn't notice but I went with my warrior and he was holding a elemental slayer weapon which would kill them in two hits. The first couple elementals I go nothing from because a guy came and killed one for me figuring I was having problems with the elemental cause I was running away. The next one I killed because I ran out of water pitchers (only took 20). Off to buy some more pitchers and back to throw them and got one fairly quickly with the next elemental I saw. It seems you can only get one pitcher from one water elemental so I killed that one and tried another and got another pitcher. The pitchers come with 40 uses and they need to be linked to a water trough to be endless. You single click on the water pitcher and a single word menu "link" comes up so you click on link then target the trough and then it should work if you are close enough to the trough. Haven't tried this yet but just thought I would tell you all so you don't have to figure it out yourself.