I think I found my Great-Aunts address. I don't speak, or write Polish.
Maybe send a Christmas card. That way you can write a short note for her to confirm if you are indeed related. It might help if you include an addressed, return envelope. Also include an e-mail address... then a younger English speaking member of the family or a friend of your Great-Aunt might reply.
A short note wouldn't be a problem for someone on the forum to translate.
Don't use an online dictionary-translator.
Have you checked the name and address in the phone book ? It might be easier to phone, but not always wiser.