I use a service called MemoToo and you can check out how I set it up on my blog.
If you go to http://memotoo.com and setup an account you can have your contacts synced with tons of services including:
- Google Contacts
- Google Calander
- Facebook (One way)
- LinkedIn (One way)
- Windows Live Contacts
- Yahoo Contacts
- Windows Mobile
- Vodafone 360 (this is a realy crap service though)
- And tones more
Its also very cheap and you only need to pay £12 per year if you have more than 50 contacts. I have 2000+ and it work just fine.
I did have a couple of hours of De-duping to do afterwords with so many services, but once you have sone that once all is good. Most dups can be deleted, but if you have a contact on Facebook and LinkedIn it is better to merge them.
The problem I have with most sync tool or scripts is that they are one time afairs that leave tonds of duplicates when you re-run them. MemoToo knows which contacts are on multiple services and automaticaly merges them once you tell it that they are the same person.