This was a bigger pain then I anticipated; I couldn't find a tutorial that showed how to use AppleScript to export data from the Address Book, but I could find an Objective C program that extracts data from it. I've never used AppleScript or Objective C, so either choice involves learning a new language. At least with Objective C, I have working source to start from. It took most of an hour to rip out the text printing code from 'contacts' and substitute in code to save vCards to individual files, but the result seems to work quite nicely. I'll clean it up and release it eventually; if anyone is interested, send me mail and I'll speed it up.