Once you find out the freguesia (parish) they were from, it will be easy to find the records of your relatives (important church records are usually located at the church office). For example, my dads relatives the Candidos were born in the village of Camarneira but the freguesia was Covoes (on occasion the parish name may change or cease to exist). Heres a copy, of a birth certificate in Portuguese but translated into English of 1898 of the town of Covoes and a death certificate of 1960 of the same town.

Website: http://www.geocities.com/