Hi Mike: I think that you can tour with just about any old bike.........However, the difference between "any old bike" and a "properly fitted touring bike" is like having to use the washroom on a bus, as opposed to using the washroom in your own home.
My wife and I did a tour of Atlantic Canada, this past summer, and there was a fellow up on the Cabot Trail with a one-speed bicycle, with wooden rims. He was in his 60's, I think, and his wife was driving a "sag wagon" for him. I never saw him climbing any of the really big hills.
There are lots of good touring bikes available but I would suggest you check out a "custom builder", just to see what they have. <www.marinoni.com> in Montreal and <www.truenorthcycles.com> in Kitchen...ers for their 2-3 hour weekend runs.
Michael