Other than Libraries

I am searching for my husband's great-grandfather and through the census, I learned he was a ship's captain. He married a woman from Newburgh, New York but in the census he lived in Brooklyn, New York. What was he doing in Newburgh when he met her? Where did they get married? John and Katherine had my husband's grandfather, William Joseph in 1889 in Newburgh, but their daughter, Johanna, was born in Brooklyn five years later. Upon review of the census again, it appeared that they had three children but only two living. The Hudson River goes from New York to Newburgh and John's a ship's captain. Hummmm. It's time to write a letter to the town historian.