How do Spyware and Malware companies get away with doing whart they do? Is anyone trying to stop it?
Specifically, the act of installing a bunch of trojans and spyware on your computer and then advertising a program that they made to remove what they put on.

the fact is that most of these companies aren’t actually companies but fake websites setup to capture your personal data such as credit card information, etc.
Ideally you should only visit websites you know and trust or use some sort of ad-block software before visiting untrusted sites.
I would strongly suggest trying out Firefox with the NoScript plugin installed. This prevents all scripts from running on a website but allows you to explicitly grant permissions to certain scripts.
Firefox – mozilla.com
NoScript – noscript.net