They should be heading up both rivers to spawn on the next moon assuming the water temp creeps on up a little. If I remember correctly peak spawn is around 55 degrees. Somebody correct me if I am wrong. Also some of them spawn down the lake from what I hear. People occassionally catch them at night in the Spring down around the dam (rip rap).
I think you are dead on Clay, from what I remember rip rap is one of the most common places for Walleye to spawn. If you are fishing from a boat, you really can't go wrong with nightcrawlers or leeches. Another great lure for walleye are jerkbaits, and these can be worked from the shore or the boat. Pre-spawn is a great time to pick up a lunker!
The part that kind of sucks about the timing, is that the striper and crappie fishing will be on fire!