I had very serious plans to relocate to Spain as well, but some people who used to live there, as well as a close frioend of mine who sells property there, convinced me otherwise (even though I still might go).
Here's some bookmarks I have that I all read very carefully, I suggest you do the same:
http://www.naarbarcelona.nl/
http://www.pisobarcelona.com/
http://www.woneninspanje.nl/
http://www.idealista.com/
http://www.spanjeforum.nl/
Good luck.