Due the 2007 Real Estate bubble Spain is not the best place for architecture positions. Most part of the architects have moved to Uk or other EU countries. Right now in Barcelona the situation is becoming better due a new rehabbing boom, but no one is constructing new buildings and the salaries aren't high at all.
For an experienced (2-3 years) the net salary is 1500 euros per months + 2 extra full pays (June and December (that's pretty common in Spain)).
That salary isn't bad in Barcelona, but you could get the double in any other western European country.