Sister is POA, not sharing info about estate

My older sister has had power of attorney for my father since 2003 when my mother died. My father passed away January 26, 2008. I already knew that he had a CD for each of us which named her as beneficiary on one and me on the other. I have the original paperwork on mine (mine was actually changed to an annuity a couple of years ago). She never made mention of reading the will, and I finally asked her about it a week after the funeral. She said it wasn't necessary, that she and I each had CDs, and her daughter and granddaughter each had one as well. I know that he had a bank account, because she wrote the check for the funeral from it. All of his expenses,which she handled, were taken care of from this account. I don't know if she was co-owner of the account. When I asked about the bank account, she said there wasn't much left. I also asked about any insurance policies he may have had, and she said he had one for about $20,000, but that they devalue over time so she wasn't sure what it was worth right now. She never offered to give me a full accounting of anything, no concrete numbers, she was just vague about everything. She has not offered to show me the will, and when I said I would like a copy, she said that the attorney has it. Apparently, he is "fixing" things so that we won't have to pay inheritance tax. Is that possible? Could something else be going on? I am totally in the dark. My dad also owned a car, which was not in the will. He told me before Christmas that he wanted his only remaining brother to have it. I told my sister this after he died, and she said she did not have a problem with that, but she still has not given it to him...she said since dad owned it, that she has to get it released. What does that mean? Should the will be going to probate? What about the car? There is no house involved. I have reason not to trust her, because my dad also told me that he wanted his brother to get some of his money when he died. He said when he told my sister this, she didn't like it and said he needed to think about his granddaughter and great granddaughter. He also told me he asked my sister twice to send his brother a check for Christmas, and she never did it. I'm sure she was counting on him forgetting about it. How do I know that she hasn't taken money from his bank account and used it for her own purposes? Do I have a right to know how she has handled his estate, and see bank account info and receipts for expenses? Can I get a copy of the will, or do I have to take her word for everything? By the way, we are in Ohio.

Your county court house will have a copy of will on record ,then the limits the time You have to file be quick or get taken (the Voice of one who has been there )

If there is a will, it would or should be filed in the county your Father lived in.
It is public record, depending on if the person holding the will has put in probate. Unless any of your Father's wishes were just verbal and not put into writing, it's your word against hers.
By the way..........your sister's power of attorney with your Father, ended on the day he passed away.