look for an irish pub, its a good start.

St. Patricks Irish Pub - Gran Via Marques del Turia 69, Valencia

Great atmosphere, great staff, no food, but who cares.
E 17. Finnegans of Dublin - Plaza de la Reina 19, Valencia

This Irish pub is run by Alan Finnegan, who worked previously in the Fiddler's Elbow in Florence, Italy. He will be more than happy to accomodate all of your drinking needs.