1st Edition:

Champions Flextiles set 1-6
Champions Super-Characters Cardboard Heroes (SJG)
Enemies

2nd Edition: 

2nd Edition Boxset - Missing Street Map
Gamemaster's Screen for Champions (2nd Edition)

3rd Edition:

Fantasy Hero (1st Edition)
Gamemaster's Screen for Champions (3rd Edition)
The HERO System Bestiary (3rd Edition)
Star Hero (1st Edition)
Magic Items
Espionage! The Secret Agent Role Playing Game
Here There Be Tigers


4th Edition:

Gm Screen - Missing Street Map (same as in 2nd Edition Boxset), Character Stand-Ups
Fantasy Hero Companion II
Horror Hero: Endless Nightmares
Western Hero




Added:
Border Crossing
The Armory Volume One
Cyber Hero