Accommodation
Hostels
Rede Nacional de Turismo Juvenil has a hostel in town, the Lagos hostel. This is located in the northeast of the town centre. It should be easy enough to find - from the bus or train stations head for the main part of town, and look at one of the maps on display there. The hostel is cheap, and seems suprisingly sociable for a HI hostel. It can be disturbingly empty in winter however.
The Rising Cock is independently-run and very actively markets itself as a party hostel. It is expensive compared to the HI hostel, but will certainly appeal more to more alcohol-minded travellers. There is free internet, and a comfortable welcoming lounge with TV. The owners have even been known to make up vats of soup for all the guests. Be aware that this hostel doesn't have a sign outside. In fact it doesn't even seem to have the name on the bell, so be ready to hunt around a bit before you find it.
In summer several pensiones offer cheap shared accomodation. Ask for details at the tourist office.