Even though the water is still in the forties, low light periods and overcast days will produce best. Once the water warms up some more, night will be your best chance. Cranks, sus. jerkbaits, grubs, senkos as well as lures mentioned above will all work as long as you keep it glued to the bottom or just off bottom. If it's cold out and the sky looks like snow, go walleye fishing.
My buddy got a 22"er this weekend on the Delaware and I heard about a few more from some weekend reports. I'm walleyeless for 2008 so far, but I have strictly chased smallmouth since the first of the year. I usually get an accidental walleye catch while smallie fishing this time of year though.
Matt