Then you may have to try manually resetting the syncservices folder by following Julian Write's post (from https://discussions.apple.com/message/9274781#9274781):
Ok, as you can't reset SyncServices in the "normal" way, you'll have to resort to the "other" way:
Although it's not advised to do so in normal circumstances, you'll need to manually delete the SyncServices folder.
Before doing so, you MUST make a backup of both your Contacts and Calendars:
In Address Book, choose *Export > Address Book Archive...* from the File menu.
In iCal, choose *Back up iCal...* from the File menu.
Then, make a backup of the SyncServices folder located at:
By backing everything up first, you don't risk losing anything.
Finally delete the aforementioned SyncServices folder and restart the Mac. This will force Mac OS X to recreate the SyncServices folder, and hopefully fix your problem.
I believe in Snow Leopard you can back up your calendar in File>Export>iCal Archive rather than File>Back up iCal as posted above.
Didn't work. Everything is still there, but contact that I've added in my phone don't migrate over and changes made on my MacBook don't show on my two other devices. This is a new problem, it happened with the latest upgrade, IOS 6.1.3. Any other ideas?
Also, should I just delete the backups and it moved my applications file onto the desktop.
I don't know what else to suggest, unless you want to upgrade to OS X Mountain Lion (available in the Mac App Store) any sync them with your Mac using iCloud. If you want to continue troubleshooting iTunes syncing you might try posting your question over in the iTunes for Mac forum.
If everything else is working as before you can go ahead and delete the backups you made earlier.