There's a cool new tool on the OC Transpo web site: a bus stop search using Google Maps. Just type in your address, and little icons pop up showing nearby stops.
You can also look up stores that sell passes & tickets.
The only bad thing: For some reason, Google Maps refers to major roads by the "Regional Road" designations. For example, Hazeldean Road shows up as "Regional Road 36", and Sussex Drive as "Regional Road 93".
Related: Ottawa Transit Guide, Ottawa Maps Guide