If you want to host a shoot, I think the best thing would be to post something on iowacarry.org. Lots of great, helpful guys on that board.
As far as the range thing, we went up as a group and introduced ourselves to the local rifle (black powder?) club, and explained that we were going to use the 20 yard berm to shoot handguns. (They were told weeks in advance by the park "ranger" that we would be there that morning). The club "spokesman" didn't like the idea of that, basically getting snotty and telling us that we would hog the range, be unsafe, and ruin it for everybody.
(At least a couple of our group were NRA certified instructors. I think he panicked when he saw that a couple of us were under 30
) Despite the fact that it was a public range, they acted like it belonged to them. We took the high road and played along, as they were there first that day, and we didn't want to make enemies among fellow gun owners. That didn't matter, as they weren't the least bit interested in our cause.
The whole thing just made me realize that there is division among gun owners, and that needs to change 'cause we're all in the same soup.