iTunes 10 for Mac: Sync contacts, calendars, and other info with iPod, iPhone, or iPad
You can use iTunes to sync your computer’s contacts, calendars, notes, Safari bookmarks, and email account information with your iPod, iPhone, or iPad. For example, if you add contacts on your iPad, you can sync to add those contacts to Contacts on your computer (or Address Book if you’re using Mac OS X v10.7.2 or earlier).
You can sync information on your device with only one iTunes library at a time. When you sync, iTunes determines whether your device or your computer contains the most recent information, and lets you choose the information you want to sync.
To sync contacts and other info with iPod touch, iPhone, or iPad:
Connect your iPhone, iPod touch, or iPad to your computer.
When your device appears in the iTunes window (below Devices), select it.
Click the Info button and select the items you want to sync.
To sync contacts and other info with iPod nano or iPod classic:
Connect your iPod to your computer.
When your device appears in iTunes (below Devices), select it, and then click the Contacts (or Info) button.
Select Sync, and then select options.
Your contact and calendar information is updated on your iPod each time you connect it to your computer. You can also update your information anytime your device is connected by choosing File > Sync iPod in iTunes.
You can also sync information wirelessly with your iPod touch, iPhone, or iPad using Microsoft Exchange. Any items you sync with these applications can also be synced with iTunes. See the documentation for Microsoft Exchange for further details.
If you have problems syncing, try syncing only certain information. For example, deselect the Sync checkboxes on the Music, Photos, Podcasts, and Video panes, and try syncing only Info.
For more information, see the documentation that came with your device or the Apple Support website.