...I hear about these floats of new cryptocurrencies but have not idea how to know when they're coming...
A lot of new coins appear every day, but only a few percent of this amount may be promising in the future. Given the fact that you don't know where you can track the appearance of new coins, you also won't be able to independently analyze new projects. So you'd better focus on buying coins that are already being traded.
Indeed, buying new projects is seems too close to give is losses in the end. It is somewhat to see that majority of these new projects are worthless and can't be trusted. And instead of getting fooled with their incentives/offers, it was highly recommended to just invest in projects that are known to their potential, not these new projects. That was better to risk our money in old coins rather than wasting it on new projects.