How do you get the pot head traders BLUE MUSHROOM?

Go over by the dmon door in the hero's guils. Near where the water is rippling, fis. You get the mushroom but trust me you wont want to give it to them. You need it to help the little boy

If you want a list of all the locations of the blue mushrooms then, 1: in front of the demon door at the heroes guild there is a fishing spot, FISH! (if you don't have a fishing rod go to the fishermens place near brightwood) 2: in the guild woods there is a man with a love letter, a blue mushroom and a look of worry, bring his love letter to a woman in oakvale, do good or evil, then go back to the man and he will give you the mushroom. 3: in the park where you kill the wasp queen, you will find a woman who wants to laugh. LAUGH! 4: at barrow fields, theres a man with a blue mushroom, you can either buy it from him for a high price, or steal it, I think theres no way not to get caught if you steal it though so I suggest you buy it. Now bring all the mushrooms to the witch in bowerstone quay, then you will start to dislike her.