With the current push for E85 fuel, so many farmers have switched to corn, including a few fields where I used to find sunflowers, one of my favorite subjects. If you know of sunflower farmers in Michigan, NW Ohio, or NE Indiana, please let me know!
Bruce, if you get desperate and want to try Kansas, I found one online this year that I'm going to head out to take a look at in August. He's got something like 65 acres and lets photographers have at it when the fields go into full bloom.
Let me know if you're interested and I'll send you the info.