This Google search should help you.

(In case you get didn't get the cool "Music albums frequently mentioned on the web" scroller that I got, it mentions Godspeed You! Black Emperor in the first spot, followed by Sigur Rós, Explosions in the Sky, Mogwai, and others)

In addition to that I'll add Broken Social Scene (not post-rock, but fellow Canadians, and great music, check out the album You Forgot It In People), ...And You Will Know Us by the Trail of Dead (more post-hardcore than post-rock, but Source Tags & Codes is a fantastic album) and Deerhoof (way more out there, not for everybody, but Apple O' is a classic if you give it a chance)

Cheers, and enjoy your adventure!