i remember having a good time in spain. There was a squatted hot springs outside of granada that was cool, everywhere I went in europe people were really open about inviting me to their squats or whatever was happening. If you've been doing it in barcelona for six years you probably know people in other communities around europe, why not just start by visiting one of them, hop from spot to spot until you find a traveling partner or two?
I second the hitchwiki thing, i would never use it in the US but I went to a hitchwiki gathering in Morocco and met a lot of really good people, had a blast. Definitely a good resource.
good luck, you all got me wanting to head back to that part of the world