Any satellite receiver capable of picking up the Astra 2d satellite will be able to give you the free to air channels (BBC1,2,3,4, ITV1,2,3,etc), but not the free to view channels (C4 & C5) which are encrypted although you do not need a subscription to view them. I believe 4 & 5 are going free to air at some time, but there is no timescale that I have seen. There is quite a thread on Sky and the free channels on the forum, can't see it at the moment, but a quick search should bring up plenty.
Mark
edit to add:
Try these links for satellite
http://www.eyeonspain.com/Secure/ForumPostsDesc.aspx?thread=2632&dev=FB29&name=TV%20in%20Spain
http://www.eyeonspain.com/Secure/ForumPostsDesc.aspx?thread=3540&dev=FB29&name=TV%20in%20Spain
and this one for other means of digital TV
http://www.eyeonspain.com/Secure/ForumPostsDesc.aspx?thread=2968&dev=FB29&name=TV%20in%20Spain
This message was last edited by Marksfish on 3/30/2008.