If you know those three things you shouldn't have much of a problem making money online.
How much money you can make is debatable, but if you're asking how to make money using them you probably don't know any of those things as well as you think you do.
Guide to making money on the internet:
Step 1 - Post shit on the Internet
Step 2 - Get people to see the shit you post on the Internet
Step 3 - People purchase/use the shit you post on the Internet
Step 4 - You have made money on the Internet
It's not that damn difficult. Work hard (or at least Internet hard, which is different from "real" hard), be diligent, don't be a fucking retard and you can make money on the internet. The question is how much can you scale what you're making on the Internet.