I always found mine in moldy cat fur. Just be patient and your cat will be growing grams of 2ce in no time.
Oh it sucked, last year my cat was just ready to grow her 2c-e (she was a big cat, I was expecting 3-5 grams from her), and she ran away....
Of course that is only what Pihkal says, and Alexander shulgin is an old man who obviously doesn't know that cats make all of this shit in their fur. He should have spared himself the time and just licked a cat.