We usually use PCB Pool for protoypes here since they generally have good service and they toss in a free metal laser cut stencil with any prototype order, but one nice little bonus is that they will also (at your request) send you photos of your PCB as it goes through the manufacturing process. If you're curious how PCBs are made, you might find these photos from a recent prototype interesting.
Drilling
Exposing
Stripped
UV Curing
We didn't request a silk screen for this board since it's just an early prototype, but the silk screen would then be added as a final step.