Where can i buy zcash coins, named as ZEC? I tried to  buy from https://www.buy-zcash.com/ but the application does not seem to work: the buy button is never activated even if i fill in a valid zcash wallet address
Try trading on exchanges for ZEC. Some of the exchanges are bitmex, poloniex, kraken, etc. Most exchanges will allow you to buy zcash in exchange for bitcoins.