LadyAda has a nice review of PCB manufacturers (http://www.ladyada.net/library/pcb/manufacturers.html
). She briefly mentions OurPCB, but I'd like to give them a somewhat more detailed and positive review. (I am not affiliated with them at all, except for having ordered from them.)
This was my first PCB ever so I wasn't sure what to expect. I spent a long time researching my fab options. I decided on OurPCB because their value seemed to be the best by a long shot: $50 setup plus about $0.15 per square inch for dual-layer boards with solderstop and silkscreening on both sides, with 10-day production time. They're in China, so another $40 for 2-day shipping. That worked out to about $110 shipped for Qty 10 6.5"x3" boards. Plus they even give you 4/4 mil width and spacing, which most places don't. It's hard to find a company that will produce boards of that size, in that quantity, for that price; the ones that come close don't have solderstop or silkscreening, or have larger minimum feature sizes.
The boards they produced were beautiful:http://www.circlemud.org/~jelson/rocket ... 0Front.jpghttp://www.circlemud.org/~jelson/rocket ... 20Back.jpg
(If possible, try to suppress snarky comments regarding my dumb routing that uses vias like they're going out of style. This was my first board, and it's mostly auto-routed using Eagle.)
The boards pictured use 8 mil traces, but a 2nd revision used 6 mil traces; I've soldered together about 15 of them so far without any failures. They're both pretty and robust. The solderstop makes them incredibly easy to solder; a friend who had never soldered anything put one together after about 5 minutes of practice.
They have no automated order system, which is good or bad, depending on whether you like talking to humans. You email them your Gerbers, and they email you back a price quote. If you approve, you paypal them money.
If you need PCBs tomorrow, they're not a good choice due to the long lead time. But for DIY projects I've been very happy with them.
They also do pick&place assembly but I haven't used that service.