For the USB Enable and Disable, Pls follow
https://www-secure.symantec.com/connect/forums/usb-device-access
http://www.symantec.com/business/support/index?page=content&id=TECH103401
https://www-secure.symantec.com/connect/downloads/sep-policy-block-usb-and-exclude-keyboard-and-mouse
How to block USB flash drives while allowing other USB devices.
http://www.symantec.com/docs/TECH104299
How to block USB devices while excluding mouse and keyboard?
http://www.symantec.com/docs/TECH161779
How to block USB hard drives, but allow reading specific USB drives in the Application and Device Control Policy?
http://www.symantec.com/docs/TECH173724
For your Second Question you can create the notification of Email for USB Device
Connect to SEPM
2. Go to "Monitors"
3. Go to "Notifications" tab
4. Click on "Notification Conditions" button at the bottom of the console
5. Click on "Add..." and select "Client Security Alert"
6. In the top of the new window, specify condition name, filtering settings (optional) and outbreak type
7. Check "Application Control Events"
8. Specify condition and damper settings
9. Check "Send email to:" and type email address to use
10. Validate
https://www-secure.symantec.com/connect/forums/sepm-report-usb-disk-activity-logged
http://www.symantec.com/business/support/index?page=content&id=HOWTO55089#v17108849