iPod Question about backing up, and playing, to/from an external drive

[pb1300]

I just got my 27 incher to go along with my MB, Apple TV, and iPhone. I am going to begin to migrate everything to the new iMac from my old one. What I am thinking of doing is after the migrate, I want to move my itunes and iphoto library to my external drive, and keep it there. Will I be able to access the files still from my MB and Apple TV? Is there any additional steps that need to be done for those two devices? I can probably just store it on my 27 incher, but I have a 2tb WD HD with firewire, so I thought this would be a good option. Thoughts/advice? Thank you.

 

[androiphone]

just having the music and photos on the external HDD then adding them into itunes and iphoto should work as flawlessly as having them on the imac