I've recently quit my job, without novice for several reasons. I was never introduced to their company's policy of how final weeks pay would be determined. She's now stating that she will not be paying me for my last weeks pay. Am I entitled to my pay for working these hours since I was never introduced to the company's policy?

Tell her you will be taking her to small claims court. Can you prove your last day?

In the US, a company must pay for all hours worked, regardless of company policy.
Tell them you will be reporting them to the Dept of Labor.

And in some states they have to pay you a penalty, in addition, if they fail to pay your final pay by a certain time.