Might be tough to locate them midday with the water warming up but I would try the islands and main lake points in the middle of the lake at night or right at first light. There are an abundance of shad holding up in these areas come summertime, you can catch just about anything around those islands. There are some decent main lake flats in that general area as well.

This map pretty much shows the deal.

http://media.photobucket.com/user/sa...f.html?filters[term]=map%20of%20Patoka%20lake%2C%20Indiana&filters[primary]=images&filters[secondary]=videos&sort=1&o=0