A quick check around the area says that all local lakes are open.
Crappie and bluegills will start to make their way to shallow, dark bottom areas on our local lakes. Most reports have water conditions as "dirty" on most lakes, especially Okauchee. But fish will still migrate towards shallow bays, boat channels, and marshy areas with dark or sandy bottoms. Sunny afternoons with a south or southwest wind will provide the best action until the water warms up.
Remember: North facing areas will be marginally warmer, and fish tend to congregate in these areas early on. Current, in the form of a creek channel, or river area will help as well.
For now, look for green weeds in shallow protected bays with a northern bank. Concentrate your efforts on the patches of weeds, using live bait suspended under a bobber. Keep you bait just above the weeds, and any visible fish that you see. I like to use waxworms or spikes on a small red hook, small/crappie sized fatheads-hooked in the tail, underneath a pencil bobber with just a split shot or two to keep the bait down. Once the water gets a little warmer, and crests 52-55 degrees, I'll start using plastics heavily, but for now, I'd stay with the live bait for a couple of weeks.