Simonr,

You can make the PWB (PCB) yourself. For "one offs" as you put it, is not a bad idea. There are plenty of methods to choose from, and plenty of information out there (milling, etching, etc.). The most popular is probably etching (chemically) and there are many different ways to make artwork, transfer it to the PCB and etch it.

The other way is to layout your board using a CAD program (expect many plugs for this one) and send it to be made. There is probably a CAD program for every living soul in the planet. It is amazing how these puppies just spring out of thin air. Anyway, you may have one or you may not. I am sure if you do not, many people will have recommendations. Just try out what best suits you (this is a good link http://www.terrypin.dial.pipex.com/ECADList.html).

There are a few places that I would consider hobby-friendly (understand that I have only dealt with very few of them). They follow (all based on double-sided PCBs):

1)Olimex (http://www.olimex.com/pcb/index.html)
$26 / 6.3x3.9in_PCB, free tooling, free mask, free silk.
Very good deal, hope it stays that way. They panelize for free also. Add $8 for shipping (2 wks).

2)CustomPCB (http://www.custompcb.com/)
$38 / 4x5.5in_PCB (x2), free tooling.
They give you 2 PCBs for that same price. They will panelize for free too. Add $8 for shipping (4 days).

3)AP Circuits (http://www.apcircuits.com/)
$74.60 for the same as in CustomPCB.
They only ship FEDEX so add $20 (2 days).

4)ExpressPCB (http://www.expresspcb.com/)
$62 for 3.8x2.5in (x3), free shipping.
They give you 3 PCBs for that price. You can only use their software.

Of these, I have use 1, 3, and 4 with good results on all. If you can wait for delivery, Olimex is by far the better deal. I am sure there are many others out there but this is the only experience I have.

I guess my point is, making your protos into PCBs is not a great deal, probably a good investment. And you can always do it yourself if need be. I actually do not wire protos anymore (well, almost). I make the layout, transfer that artwork to PCB, and etch it. The additional time invested is not too great, but it really pays off when debugging messy wires.

Hope this helps.