Go to the SD and ND game and fish websites, and search around for two statistics:

1) Spring Crowing Counts (gives an idea how many breeding adults survived the winter)
2) Late Summer Roadside Brood Counts (how many chicks are being spotted)

Tally the best spots that seem to have birds, and just get a hotel somewhere nearby. If you are from the South, don't bother coming up after mid-Nov. as you won't like the weather and it can get dangerous if you don't know what you are doing. Just go in mid-late October and have a good time on public land, ask farmers for permission, ask around a small town. People are used to it, they want your money to support the economy, and you'll find your 3-bird limit if you want to hunt hard all day.