I was let go from a company where, employees stated things that I said, that I did not say, It sounds like the things that was said, were by a group of three employees, that said the very things that they said I said, How can I prove defamation, and when I ask to see my personnel file, will this information be inside the file. I will ask for a copy of my file, will I get a copy of everything I signed and didn't sign.

No one here has any way of knowing what is in your personnel file. Did you have a contract, belong to a union? If not, the personnel file belongs to the employer. Until you take action against them you do not have a right to review it. The other side of this is why would your employer hand you anything you could use against them? You may need an Attorney to get the file released.

It sounds like "he said, she said." You will need to prove that whatever was said was the only cause of your termination, that you were harmed financially, that these people caused the damage.

What could you possibly say or have said that three people went to your employer and the info was so damaging that you were terminated? Employers usually sort of brush this stuff off and tell you all to shut up.