You can buy KDA on Coinmetro/Bittrex but they require KYC/AML so they are not anonymous.
Personally I use Hotbit to buy, an unregulated exchange, it works fine but you have to be careful with those exchanges as they sometimes exit scam or do other shady stuff. Just buy and move to your personal wallet. Never leave funds on an exchange or deposit too much at once.
Kadena has announced that they will join a major tier 1 exchange soon, the price will probably increase when that listing is announced.
I have been using
https://qic.quora.com/ or their Telegram group for coin ideas. Some of the shilled stuff is good some terrible but it's free and sometimes they have some gems. It's not all bad if you don't have much time but I wouldn't buy every coin they push.
ICO can range from good to bad, depends on the project, I have heard people talking about Studentcoin a lot but I did not look into it. Some claimed it was a scam. I don't know anything about it.