This discussion actually should below ni the altcoin discussion but well let me answer here, you can find so many airdrops in this section:
https://bitcointalk.org/index.php?board=159.0 just see the topic with tag [AIRDROPS] be sure that the airdrop still ongoing before making a submission. but one most important thing, before installing their wallet, if they use their own blockchain for their coin, scan it first to make sure that you're not going to install a virus, but if they use ethereum smartcontract, everything will be fine.