Hi Rab. I don't live in that part of the state but i might be able to help you out just a little bit. Most public lakes in this state have quite a bit of surrounding land that is owned by the county. I have never been to Red Rock, although i would love to fish it someday. So i really know nothing about it.
I have a website you can look at that will show you some property lines.
http://beacon.schneidercorp.com/?site=MuscatineCountyIA . Pick Iowa as the state and choose Marion county. Start with the map and zoom in a little. Check rural imagery and make sure the parcels box is checked. You can then zoom in to see some of the surrounding landowners. Click the blue button with the letter I on it and any parcel you hold the curser over will show you who owns it.
Other lakes i have looked at usually show the county or someone owning the timber surrounding the lake. This lake has some surrounding timber but it tells you no parcel found. You would have to check into it but i would bet all those parcels are owned by the state and are huntable, except for the two state parks.
Thats about all i can help you with. Hopefully you can get some local guys answer this thread.
These other two sites may help you out more about figuring out the hunting oppourtunities. Looks like alot of land to get away from people. Although you do have a major city closeby. Des Moines.
http://www2.mvr.usace.army.mil/RedRock/Maps/default.cfm
http://www2.mvr.usace.army.mil/RedRo...ingMap_000.pdf
Jerry.