Ok, to keep this brief, does anyone have any recommendations for getting to Barcelona from San Francisco cheaply? I am looking to go in Sept. and return in December. I understand that there are a multitude of inter-Europe flight that are really cheap. With that being said, what airlines/destinations would offer me the best deal to use an intraEurope flight.

I have done a lot of research so far, but the people on this site seem to have a wealth of knowledge. Thank you in advance.