Rosemary and Thyme:
Twenty-three -23- twenty-three episodes, 31 Aug. 2003-27 May 2006. Quite a few on DVD (Two sets), but don't have the details.

I know that I have seen only about ten on PBS, not sure how many were shown on the Spokane outlet which we get in western Canada.
We also get the Detroit outlet on our broadband, but I have no idea whether they carried that series. I know that programing of that kind varies from station to station depending on their budget and their directors.