There's 2 outfits that charter on Minnewanka:
Brewster's Minnewanka Lake Cruise has 2 new Hewescraft charterboats that are superb fishing machines. Their head guide is Blair, and he's been guiding on that lake for many years - excellent guide.
http://www.explorerockies.com/minnew...r-fishing.aspx
The other company is Banff Fishing Unlimited. They have older equipment, but also have some excellent guides. Jeff is terrific and very experienced on Minnewanka as well..
http://www.banff-fishing.com/minnie.html
Note, - I work for the company that owns the first outfit, but both will get you into fish.