Jennifer - Your best bet here in Albuquerque for supplies is Camera and Darkroom (3225 Central Ave. NE; 505-255-1133) (this is a new location for them - they moved a few blocks this fall). They also have a shop in Santa Fe. They don't have real extensive large format inventory, but should have most films. It certainly wouldn't hurt to call ahead to check on stock/availability.
If you want to get some processing done here in town - my experience is with E-6...Carl's Darkroom and Camera Graphics seem to be the most widely used by pros.