Is it possible we can Add External Link into the Automation Web page? I still find a way to do so...if anyone can shed light on this is much appreciated.
At least in the ASD you have the option to add a link to the service blueprint
I believe there is a link custom property that will convert what you type into a link per this thread Custom properties and HTML. I have not tested this personally though.
If you want to change anything on the vCAC\vRA front page, the change has to be done on the Identity (SSO) appliance. AFAIK there is no easy way to do this, like just editing some html files on the appliance.
A hint on how this can be done can be found here: http://kb.vmware.com/kb/2091309
Changes to the request pages or similar, which you see after logging in, have to be done on the web server, since those are iframes loaded from there. I have not done any of the above myself, yet, although in the near future I will want to edit the front page as well, by adding a link pointing to a user manual for my users, hosted on an intranet site.