I'm in Ottawa as well guys. Never mind finding a specific buick tuner here in this city, you can get some dyno time here though and there are a couple of us who can help out.
If you don't already have one, I'd suggest a new modern chip which will at least allow some parameters, fueling and timing changes as well as an adjustable fuel pressure regulator for starters, upgraded fuel pump wiring, the list goes on and on.
To the oroginal poster, what are the upgrades done to your car?