Guides
Most advice creators find about contracts and money is published by the people taking a cut of it. These are written by someone with no agency to protect, with the sources cited so you can check them.
Contracts
Taxes
Chargebacks
Business of creating
Nothing here is tax or legal advice — I'm not an accountant or a lawyer, and I say so on my page. What you get is the arithmetic done carefully and the primary sources linked. For anything you're about to sign or file, use a professional.