If you go to my blog at:
I have posted extracts from the timetable of rede-expressos, a national bus company..
This company offers a through booking service from both Lourinha and Peniche to Povoa da Varzim, daily except Sundays and Public Holidays, although you will have to route via Lisbon and Porto.
Click on the Image to enlarge:
It appears reasonably cheap and at least you don't have to worry about changing between rail and bus stations.
Bus Company site:
http://www.rede-expressos.pt/0010.asp
