How do I make Evolution check and notify new emails, without keeping main UI open? [closed]
As far as I know this is not possible at the moment. There is already a bug report at launchpad: https://bugs.launchpad.net/ubuntu/+source/evolution-indicator/+bug/508608
You could try installing 'mail-notification-evolution', its supposed to provide support for Mail Notification. I had some problems using it, but some people have had better luck than me.
sudo apt-get install mail-notification-evolution