Samy's Camera in Santa Barbara does mail-order E/6 and C-41. $1.50/sheet for 4x5 c-41. Very clean processing too, cleanest I've had so far!

they can be reached at (805) 963-7269 Mon-Sat(Closed Sun) 9:30am-6pm PST

I've attached the pdf of their c-41 and e-6 order forms