So, for those of you who were wondering, I was on vacation last week. Hence the dearth of new posts...
In my inbox when I got back was a message from a friend in the business pointing out this handy on-line directory of outsourcing service providers. It's called "OSourceBook 2008." It is apparently a pay-to-play directory so the results may not be perfect if you're searching for small companies or for companies in emerging markets; but it's a decent search engine. I used it to search by vertical and country for some companies I know well, and they popped up as expected.
You can also use it to search, for instance, for IT Service providers in Belgium (there is one) or for testing service providers located in Iceland (there isn't one). Not many lists of service providers I've seen offer such easy cross-sectioning of the industry.
No affiliation, just an interesting site.