Hi sleeper.  I agree with the above.  It's very easy to fall into the trap of buying something which is not legal to live in.  However, there are legal properties available even if they may be a small percentage of what's advertised.  If I were you, keen on coming to live here but (quite rightly) somewhat alarmed by the comments on here (and they're justified in the main) then I would talk to Ton Battel before you go looking and get him to arm you with the catches to look out for.
I have to say that I've always found the Catalan people friendly, helpful and generous especially if you make the effort to learn Catalan or even Spanish.  Don't be put off, just be very very careful.