The first thing about ICOs you have to know is that they are incredibly controversial. And with good reason. They try to balance between being "securities" (you own part of the project) and "not securities" (SEC does not regulate them). The tokens for the most part offer only vague promises and so they are impossible to valuate.

It's never too late to start because there are always more coming out. https://www.smithandcrown.com/icos/ is a good listing of what's out there. But just as an example, I recently put 0.1 ETH into LAToken expecting the value to increase once it hit the exchanges...so far more than half of the value of this token is gone. I could have bought the token for less than half the price just by waiting till it was on an exchange.

The process of actually purchasing the ICO was pretty cool though because it's a great way to experience what Ethereum is capable of. I just use Jaxx as my own wallet to make the purchase on the ICOs website and then confirm that the token is in my wallet by using https://www.myetherwallet.com/.

Just don't take my information here as an endorsement of ICOs. As I'm sure you've heard, most (if not all) of them, I'm convinced, are crap.