Hi John, If you have been living here full time for a year and a half you are deemed in law to be both a resident and a fiscal resident but you still have to do the paperwork! Now is the time to do a Declaracion de Renta (tax return) to keep within the law.
See also:
N.I.E. (EX14) / RESIDENCIA (EX16)
Application Forms and the
Regulations Governing EU citizens in Spain document.
http://extranjeros.mtas.es/
For forms - Click: Modelos de Solictudes
Or direct link
http://extranjeros.mtas.es/es/general/procedimientos_Solicitudes_index.html
For the Regulations document (from Home page)
Click UK flag & R?gimen de los ciudadanos Comunitarios en Espa?a