When you go to the Outlook-Exchange training signup, you will click on the session group you want, then click on 'Sign up for work session or class'. You'll see a drop-down menu that says: '<--Select Name-->'. If your name appears in the drop-down list, you can select it and continue with your registration.

If your name does not appear in the drop-down list, click on '<--Add New Name-->', which is at the top of the drop-down list. You can then add yourself to the list and register for the training session you want.