Tips on the Ottawa course itself...

Tempted to enter this race. What can I expect from the course?

Is it flat or hilly, and what kind of route does it follow around the city?

check out this website http://www.runottawa.ca/index.php/en/interactive-course-map [runottawa.ca] and click on marathon or half and you will see the elevation chart on the bottom... Also this marathon was the fastest marathon in 2008.