Spanair offers a "Spain Pass" which allows 3 legs within Spain for $195. Travel is restricted to certain cities, but the majors are all included. Additional legs can be added for about $50. They will require you provided your round trip ticket number so they know you are a visitor to the country since this offer is not available to natives. Their website provides all the info you need regarding schedules etc. so you can see if this option works for you. I'll be travelling to Spain in October, and I was much relieved to learn of this pass since it will allow us to make the most of our 17 days there.
[ 04-27-2001: Message edited by: MadridMan ]