Have you ever gotten a Facebook group invitation saying something like “I lost my cell phone. Please give me your number.” Or “I just moved; here is my new address.” What if there were a way to get Facebook to update your address book automatically. You can and, best of all, it’s free.

Plaxo is a tool that can connect your address book with Facebook. But it does a lot more than that. It can also purge duplicate addresses and sync your address book with your iPhone or Blackberry.

Here is how to sync Plaxo with Facebook:

Step #1 Sign Up For Plaxo

Go to Plaxo.com and click “sign up now“. Follow the instructions. It’s pretty straight forward.

Step #2 Sync Plaxo & Facebook

You can do this by going to settings -> Facebook or click here.

Step #3 Connect Plaxo With Your Address Book

The true magic comes when you connect Plaxo with your address book. Whether you use Mac’s address book, Yahoo, or Outlook, Plaxo can keep your address book up to date automatically. To sync the address books click here and then click “add sync point” at the bottom of the screen.

Other cool things Plaxo can do:

• Purge duplicate entries from your address book.
• Keep your address book up-to-date. When you connect with someone, Plaxo will keep both of your contacts for each other up-to-date.
• Synchronizing your address books. Do you have more than one computer? Plaxo can keep all those computer address books synced. It even works with the iPhone, Palm and BlackBerry.
• Blog re-syndication: Plaxo can re-syndicate your blog and podcast which is great for search engine rankings and growing traffic.