i have got them trolling lures @ 30 fow suspended in 80 fow at travers before was fishing for pike and got lots of wallys that way one of my fav ways to catch them
Best action I have ever had was trolling flourescent rapalas in 4 feet of water over a 6-8 foot weed bed. It was during a heavy rainstorm and they were insane. We caught 10-15 large walleyes 50-75 cm in a matter of 20 min. till storm quit. We did not get any small fish. This repeated itself several times but we only caught them during heavy rain. Might have worked at night but it was a hard spot to get to during the day so never tried.
I usualy catch them right on the bottom, with either a slip sinker rig or a jig if I cant feel it bumping on the bottom I'm usualy not catching many fish. I've recently discovered upstream trolling with large crankbaits. I am not sure how close to the bottom these get but it sure seems to work well so maby they will swim up a bit for a large meal.