I did mean in general - not necessarily for an American
I did know an American family here who had to go back to the States very quickly because they couldn't get legal permission to stay & work - even though the father's mother had taken Spanish nationality many years previously & lived here
they were told that they would have to return to the States & apply through the Spanish Embassy there
I dare say that's the only way for Rachel to find out for sure - contact the Spanish Embassy
The problems arise because Spain is a Schengen area country. Before Schengen was set up, Americans in Prague used to get a train to Dresden across the German border and back again after getting their passport stamped. That allowed them to continue residing in the CR until the need to make the hour-long trip came round again.
After Schengen that was no longer possible and there was a great exodus of U.S. citizens. The Czech Police actually started deporting those who had stayed without fulfilling the new visa requirements. People with Schengen visas -which are valid for 90 days -are not allowed to reside or work permanently in any of the Schengen area countries which includes all EU states apart from Ireland and the U.K., I think.
As someone said earlier, EU citizens come first in the job market, then other nationals.
An American friend in Prague was unable to get permission to work at a student summer camp in the UK a year ago although she had experience of working in this field.
Would the Spanish police actively look for those living and working illegally, I wonder?