There are places called Alcobaca and Nazare about 110km north of Lisbon on the coast. If these are your destination -
The bus is much quicker than the train (two hours journey) and these run ( I think) from the LISBON SETE RIOS bus terminal four or five times a day to Nazare and five or six times a day to Alcobaca. Ticket is €8 - €9. You can get the times from this website
http://www.rede-expressos.pt.
The SETE RIOS bus terminal is about 1km to the west of Entrecampos and is not on a direct bus line from the Airport so you may find it easier to take a taxi.
(NOTE - TO ANYONE READING THIS! The Rede-Expressos website does not so far as I can find actually tell from where in the large city of Lisbon its buses start!)
There is a train station called Valado - Nazare - Alcobaca.
This station is about 5km from both Nazare and Alcobaca. I do not know any information about a local bus or taxi as I have never visited these places.
Trains run from LISBOA ENTRECAMPOS but you must change trains (transfer) at CALDAS DA RAINHA.
You can see in the messages above how to get from the airport to Entrecampos station.
There are only FOUR trains a day at these times:
0545 not on Sundays arrival at Valado 0847
1026 every day arrival at Valado at 1347
1426 every day arrival at Valado at 1647
1626 every day arival at Valado at 1924
I hope this helps you.
Good luck.