How do I export my iPhone's call logs?
How about iPhone Call List?  (You can download a free copy in the link)  

I haven't tried it myself yet (I'll as soon as I get home), but it seems the app you're looking for!


  iPhone call list to Mac Transfer fully support latest iOS 4.2, iPad,
  iPhone OS 3.1.3, iPod touch FW 3.1.3, iPod nano 5G FW 1.0 and iTunes
  10.1.