Law /
Polish Citizenship for a foreigner whose parents was born in Poland [174]
If your Dad is Polish, your Polish. Get copies of your parents birth and marriage certificates, any old expired Polish passports your Dad has or any Polish gov documents he has. I assume your father at least has a Polish birth certificate if he was born there which will make it easier.
You have 2 options, work with the consulate in your country or get a lawyer in Poland. You can search this forum or Google for the different lawyers if you go that route.
You will need to get your Polish citizenship confirmed and you will need to have YOUR birth registered in Poland as well as your parents marriage if your mother isn't Polish. Once this is done, you can go to the consulate and apply for a PESEL and Passport with your confirmation letter and POLISH birth certificate. As of now this has to be done in person, they'll take your fingerprints (which is why you have to go in person) but they can usually mail the passport to you. My only hold up for some reason, Polish govt wanted a copy of my US Passport too (i'm guessing to prove my identity) and I had to get an apostle certifying it as a copy.
I just went through this and I actually got my passport in the mail today. My dad is the only polish parent and both my grandparents live in Poland. I was lacking my fathers polish birth certificate so I used a lawyer in Poland who did some research and got me the confirmation in about 3-4 months. I then had to travel to the consulate and it took 4 weeks to get my passport.
My total cost: about 800 US Dollar. It will be cheaper (3-400 USD) if you can do it all through the consulate.