I've always used: http://www.apcircuits.com/
They have on-line calculation of cost, they offer a bare-bones "prototype" service (no extras) as well as their upscale full silkscreen and solder-masked boards using different laminates (GHz rated stuff) ...
For their prototype service, they have a restricted set of drill bits and non-solder-masked and no silkscreen (keeps costs down) and like a two-day turnaround with status updates.
Basic Prototype data received after 11:00 AM Mountain (13:00 Eastern) will be queued for formatting the next business day and ship the business day following that.
I like using them because there is no 'human' involved negotiating price, they have on-line price calculator: http://www.apcircuits.com/ap/calculator
When ready to order, just FTP in the files zipped up or use their xfer utility to send in the Gerbers with their order form.
I hesitate to mention this, but, I've got a friend who operates a small company with Juki 'pick and place' (SMT placement line
) equipment ...
Update: Looks like setup charge is a little higher for APCircuits but per sq inch is a little lower and of course the turn around time for the batch guys could be like 20 days vs 2 or 3 for APCircuits ... there are other trade-offs, as the batch guys will do silk-screening and soldermask (I think) for that 2.50 a sq inch - that's not bad ... good find.