EU residents and those covered by the European Economic Agreement (Norway and Iceland) don't need residence visas. But, if you intend to stay in Spain for an extended period, you will need a Foreign Identity Number (Número de Identidad de Extranjero, or NIE) and may also need a Residence Card (Tarjeta de Residencia). You can apply through the Oficina de Extranjeros / Oficina d'Estrangers (http://extranjeros.mtas.es, available in English, French and Spanish). Once you have settled in, you'll want to head over to your local city hall (Ajuntament) office and add your name to the Padró Municipal d'Habitants, the residency registry which entitles you to other benefits.