http://www.in-fisherman.com/walleye_insider/articles/wi0507_TrollNight/
You might want to check out a couple of the Infishermans video's on trolling techniques.
Alot of your speed is determined how the lures your using react at certain speeds. Many bites are triggered from the change in speeds you get when you do your S turns etc.
Are you going to be running lures on bottom bouncers or flat lining, planer boards, on line planer boards, down riggers.
If you can go on a charter on Ontario or Erie and let the guy know you want to pick his brain. Most of these guys are pretty good about it.
I sat down next to a guide(didn't know it at the time)onenight in a bar up in Pulaski, and started talking with him about Salmon fishing, next thing I know he's taking me and my kid out in the morning. He didn't have anything scheduled and didn't feel like fishing alone.