How do I keep my contacts separate? How do I keep my Gmail contacts off my phone (Samsung Galaxy S if it matters) and at the same time keep my phone's contacts off Gmail?  I don't normally do email from my phone, and when I have had to log into my account, it automatically downloaded all the contacts.  I don't want to search through a bunch of email-only contacts to find the person I need to call.
In the Settings -> Accounts &amp; Sync, select your gmail account, in there you will see "Sync Contacts". You can uncheck that and the device will not sync your contacts to gmail, nor will your gmail contacts sync to your device.

As onik said too, you can have it show only people with phone numbers too.