Here's yet another method of migrating your Outlook (on your PC) contacts to Address Book on a Mac. It's a bit of a workaround, but it's free.
Download Thunderbird for the PC, and import your Outlook contacts into Thunderbird. Then export the contacts to a .ldif file on the PC. Transfer the .ldif file to your Mac and import the .ldif to Address Book. Done.
[robg adds: There are many other hints (1 • 2 • 3 • 4 • 5 • 6) here concerning moving Outlook's contact data to Address Book.]
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