Roca Espana, German guidebook to Spain
The best overall guidebook I found for Spain was this one, Roca Espana, which I bought in Munich. The guidebooks by Rockfax had more routes and information about camping and travel for individual areas, but this one book covered the entire country.
We used the directions from here to find individual areas, like Sella, Jerica, Montanejos, and the Sierra des Prade and then bought indiviual guides to certain of the areas.
As we were initially fleeing the rain, we continually headed south in hopes of warmer and dryer weather.