Spain is on sale from many airports in the USA and some of the best deals are from western states. United Airlines and Air Canada have Phoenix to Barcelona or Madrid on sale in the $540s to $560s for departures January to early April. Madrid is also a cheap destination from Phoenix, whereas, Madrid is $1,200+ from LAX and SFO. These cities only offer discount fares to Barcelona with Star Alliance today.
Loyalty Traveler – LAX/SFO to Barcelona $433-$513 Star Alliance/Oneworld Jan-May (Nov 16).
United Airlines Phoenix PHX – Newark EWR – Barcelona BCN – Toronto YYZ – Phoenix PHX
United Airlines Phoenix PHX – Newark EWR – Madrid MAD – Brussels BRU – Chicago ORD – Phoenix PHX
Momondo.com search pulled up $508 to Barcelona and $527 fares to Madrid with United Airlines/Air Canada for these same dates.