I would definitely recommend learning the language sooner rather than later if you are thinking of moving to Spain to live. There may be a high level of English speakers living in Spain, but you will enjoy your time much more if you are able to speak the lingo. I recommend openeuropa (check out their website) who provide first rate online courses that you can start before you arrive and continue while you are in Spain. All the tutors are native speakers and they get you speaking fast.