open source shall set you free:
This should show you how to import your yahoo address book into your Mac OS X Jaguar AddressBook (v3.03):
1) http://addressbook.yahoo.com/ go to import/export. Export your address book into Netscape Addressbook format, aka LDIF.
2) open Mozilla for OS X (http://www.mozilla.org/ to get the latest stable version, 1.4 as of this writing). at bottom-left-hand corner, click on address book icon. Go to Tools --> Import, pick LDIF, choose the yahoo ldif file. let it import all your stuff, verify all your data is there.
3) Still in Mozilla Address Book, Tools-->Export --> LDIF save yet another .ldif file.
4) Open AddressBook.app in Mac OS X, Import --> LDIF, pick the .ldif file generated by mozilla.
5) bickity-bam, you should be done.
==> going through mozilla appears to get around the AddressBook.app "hanging" bug i mentioned in my previous (anonymous) post, while trying to import a yahoo-generated LDIF file.
MUWHAHA iSync, here i come >:]