I fish a lake that they stock each spring with rainbows. I can usually catch them on the same
type flies I use for the gills - namely nymphs. You could run into a problem if you are trying to fish from the shore or by wading as the fish may be further out and deeper than you can reach. Why not take a spinning rod, an egg bobber filled with water and work along the shore until you hopefully find them and then see if it is practible to switch to the long rod.

Tim