Android - How do I keep my contacts separate?

In the Settings -> Accounts & 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.

There's an option to only show contacts that have a phone number, you can set it in Contacts -> menu key -> Display options. This will hide the unnecessary contacts but keep your email synced.

Here is another option similar to @onik's reply ...

In the Contacts -> menu key -> Display options, there is a list that says Choose contacts to display. For example, Google, Backup Assistant + Contacts, Preset, Hotmail. There is a down arrow on the left of each item. Click the arrow and panel appears with All contacts and a check box. Uncheck the box, and those contacts will not be displayed in your list.

• This is for Android v2.3.5
• On Verizon
• Motorola