Hello
I have been into the hobby for the past ten years and have many source books, old rulebooks and escape from goblin town rulebook. I don't own the hard cover Hobbit rulebook.
I have a Cirith Ungol, Angmar and an Uruk-hai scout army.

My question is:
Have units from these armies profiles changed and is there new equipment they can now take such as warhorns?

Depends which sourcebooks you have. The fallen realms sourcebook is the most up to date for Uruks, Mordor for Cirith Ungol and Moria and Angmar for an angmar army. As far as I can tell, only the Black numerorians and morgul knights can take war horns for any of the lists that you've asked about.

Thanks for clearing that up.
I thought the hard back Hobbit rulebook might have changed profiles and wargear options of units in the old source books.