I would like to change the look and feel of the logout and help buttons on the user interface. Specifically, I'd like to change the borders of these two buttons. Any idea where I can find the definition and customization of these buttons.
All native look and feel is managed by css style sheets.
Read idm pdf related to change branding you will get all info there.
Check css file from you installed idm location : idm_directory\styles\style.css
All branding sample is avaiable at idm_directory\sample\rebranding