The full Lagos Bus timetable is now available online in pdf format at:
http://www.aonda.pt/
Click on "Horario":
and then the line you want.
You can then open and/or download the files in pdf format.
Updated: 13th May 2008.
The link is dead for some reason.
In the interim have a look at this link...only in Portuguese:
http://www.cm-lagos.pt/portal_autarquico/lagos/v_pt-PT/pagina_inicial/destaques/onda_novos_trajectos_horarios.htm
