I use 2 main companies for my affiliates to make money and one has been bullying me lately, telling me to take things down off my page, which are not in violation of their terms of service, and delaying my payment (its been months now, and they say they are still "investigating" my account). I want to take action against them (I have 2 addresses, they don't realize that I live in the same area as their headquarters, so it would be easy to file suit). How do I prove how much money I've made to a court of law? Screenshots could easily be photoshopped, so thats not really proof. What if I launch a civil suit against them, and they delete my account and say it never existed? How do I prove it existed, and how do I prove how much I made? What would you do? I'm not going to name the company yet until after the next payment date. If they don't pay me by then, then I'll take legal action and of course start naming them on all the forums. I don't want to jump to conclusions because they have a good reputation from what I've seen online, but they are definately holding my money which I made legally without violating any terms of service. It's almost like they want to know how I'm doing it so they can steal my ideas and copy me.
You need to talk to an attorney. He can tell you what would be accepted as evidence in your jurisdiction and how to proceed in such a way that you are likely to win. He will also be able to do a legal analysis of the terms and conditions that you agreed to, to both be sure that you are actually not in violation, and to make an educated guess at what the other guys will argue in court. Note that an attorney would almost certainly tell you that if you are going to take legal action it's foolish to say anything on forums. Anything you write can be used against you, and it makes it much less likely that the affiliate program will settle with you.
Forget about suing them, it isn't going to worth the cost - unless you are talking a small sum that can be handled in small claims court. They've told you to take things off your page and you haven't. That alone could give them cause to terminate you - and perhaps not pay you. Most have a TOS that allows them to terminate you at will, without cause. If you don't want to follow their rules, find another company.