According to Ken Rockwell, NCPS will give scans of slide film that surpass the D3 for sharpness. There's a link for the "ken rockwell scans." I have used Dwayne's photo and they do a wonderful job and provide scans. The service is fast too.
I just Yelped:
Pardees
Photo Source
Camera Arts (closed?)
Cali Color
Ritz
On Dead Link Removed does E-6, not sure about C-41, maybe Richard Photo Labs.
Sorry that's the best I could do, the last time I did E-6 or C-41 was a while ago when I had access to a Wing-Lynch. Then it was easy-peasy, but now I don't know, haven't tried any in my CPP-2.
Hello-
I use Dale Labs of Hollywood Fl. Dalelabs.com
They offer great print and slide developing. If you send them prints using their regular service you will get Kodak Ektacolor Edge Paper and their Pro Proofing serve comes out much better with Kodak Endura paper.I have tried tons and tons of mail order labs and found this to be the best.