The listing I found (via the Adventure Path filter in the Archives) indicates which issues they came from. Specifically 156-168, and 170-175.
I also had no idea what it was about, exactly. The only reference I'd seen to it was in the character builder 'Backgrounds' section. I grabbed them all today, independently of my issue archive. A lot of the encounter and monster math will be out of sync with current thinking, but it might still come in handy someday. Like if I ever take a blow to the head and decide that 'Dragon War' is a good theme for a campaign*.
* I'm only knocking it because I had a DM that turned EVERY campaign into a Dragon War (think Dragonlance novels meets a Greyhawk/FR mashup homebrew), and I now hate it thoroughly, just as a general concept.