Here are some useful links to websites related to the area:

Caballo Blanco horse riding & trekking center:

Bootlace Walking Holidays,
spectacular mountain walks in Spain and Morocco:

Rambutan Hostel, Granada:

Trekking & scrambling holidays in the Sierras of Southern Spain
with a qualified mountain guide:

Casa Caracol a great hostel in Cadiz:

A resource for hostel managers/owners, 
and people who are interested in information about how to open new backpacker hostels:

Natural campsite and donkey trekking in Asturias: