My step-father recently passed away. Prior to his passing, he told one family member that his will was something he wrote on a piece of paper and signed by he and his wife (my step-mother) with no lawyer involved. He told another family member that I was the executress of the estate, and provided for in the will. I have no knowledge of either situation and his wife immediately distanced herself from family upon his death, even though we had an excellent relationship up until that point. Is there any legal way to be able to verify the contents of his will in order to ensure that his wishes are carried out? Does the will, even though hand-written, have to be filed with the court?
Would I be automatically notified if I were the executress?

Holographic wills are acceptable, but they are easier to contest. For a will to be "official" it would have to be filed in probate court. However, its not necessary to do so if the estate is small and the distribution is amicable.

What you need to do is get a hold of that will. Generally the executor is given a copy. If you don't have a copy, then you will probably need to go to probate court with the other 2 familiy members as witnesses that they say or were told of the will. If you need to do that I suggest you get a lawyer.